Truth is the property of being in accord with
fact or
reality
Reality is the sum or aggregate of all that is real or existent within a system, as opposed to that which is only imaginary. The term is also used to refer to the ontological status of things, indicating their existence. In physical terms, r ...
.
[Merriam-Webster's Online Dictionary]
truth
2005 In everyday language, truth is typically ascribed to things that aim to represent reality or otherwise correspond to it, such as
belief
A belief is an attitude that something is the case, or that some proposition is true. In epistemology, philosophers use the term "belief" to refer to attitudes about the world which can be either true or false. To believe something is to take ...
s,
proposition
In logic and linguistics, a proposition is the meaning of a declarative sentence. In philosophy, " meaning" is understood to be a non-linguistic entity which is shared by all sentences with the same meaning. Equivalently, a proposition is the no ...
s, and
declarative sentence
In linguistics and grammar, a sentence is a linguistic expression, such as the English example "The quick brown fox jumps over the lazy dog." In traditional grammar, it is typically defined as a string of words that expresses a complete thought, ...
s.
Truth is usually held to be the opposite of
falsehood
Deception or falsehood is an act or statement that misleads, hides the truth, or promotes a belief, concept, or idea that is not true. It is often done for personal gain or advantage. Deception can involve dissimulation, propaganda and sleight o ...
. The
concept
Concepts are defined as abstract ideas. They are understood to be the fundamental building blocks of the concept behind principles, thoughts and beliefs.
They play an important role in all aspects of cognition. As such, concepts are studied by ...
of truth is discussed and debated in various contexts, including philosophy, art, theology, and science. Most human activities depend upon the concept, where its nature as a concept is assumed rather than being a subject of discussion; these include most of the
science
Science is a systematic endeavor that Scientific method, builds and organizes knowledge in the form of Testability, testable explanations and predictions about the universe.
Science may be as old as the human species, and some of the earli ...
s,
law
Law is a set of rules that are created and are enforceable by social or governmental institutions to regulate behavior,Robertson, ''Crimes against humanity'', 90. with its precise definition a matter of longstanding debate. It has been vario ...
,
journalism
Journalism is the production and distribution of reports on the interaction of events, facts, ideas, and people that are the " news of the day" and that informs society to at least some degree. The word, a noun, applies to the occupation (pro ...
, and everyday life. Some philosophers view the concept of truth as basic, and unable to be explained in any terms that are more easily understood than the concept of truth itself.
Most commonly, truth is viewed as the correspondence of
language
Language is a structured system of communication. The structure of a language is its grammar and the free components are its vocabulary. Languages are the primary means by which humans communicate, and may be conveyed through a variety of ...
or
thought to a mind-independent world. This is called the
correspondence theory of truth.
Various theories and views of truth continue to be debated among scholars, philosophers, and theologians.
There are many different questions about the nature of truth which are still the subject of contemporary debates, such as: the question of defining truth. If it is even possible to give an informative definition of truth. Identifying things are
truth-bearer
A truth-bearer is an entity that is said to be either true or false and nothing else. The thesis that some things are true while others are false has led to different theories about the nature of these entities. Since there is divergence of o ...
s and are therefore capable of being true or false. If truth and falsehood are
bivalent, or if there are other truth values. Identifying the
criteria of truth
In epistemology, criteria of truth (or tests of truth) are standards and rules used to judge the accuracy of statements and claims. They are tools of verification, and as in the problem of the criterion, the reliability of these tools is disputed ...
that allow us to identify it and to distinguish it from falsehood. The role that truth plays in constituting
knowledge
Knowledge can be defined as Descriptive knowledge, awareness of facts or as Procedural knowledge, practical skills, and may also refer to Knowledge by acquaintance, familiarity with objects or situations. Knowledge of facts, also called pro ...
. And if truth is always
absolute, or if it can be
relative to one's perspective.
Definition and etymology
The English word ''
truth
Truth is the property of being in accord with fact or reality.Merriam-Webster's Online Dictionarytruth 2005 In everyday language, truth is typically ascribed to things that aim to represent reality or otherwise correspond to it, such as belie ...
'' is derived from
Old English
Old English (, ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlers in the mid-5th c ...
''tríewþ, tréowþ, trýwþ'',
Middle English
Middle English (abbreviated to ME) is a form of the English language that was spoken after the Norman conquest of 1066, until the late 15th century. The English language underwent distinct variations and developments following the Old English ...
''trewþe'', cognate to
Old High German
Old High German (OHG; german: Althochdeutsch (Ahd.)) is the earliest stage of the German language, conventionally covering the period from around 750 to 1050.
There is no standardised or supra-regional form of German at this period, and Old High ...
''triuwida'',
Old Norse
Old Norse, Old Nordic, or Old Scandinavian, is a stage of development of North Germanic dialects before their final divergence into separate Nordic languages. Old Norse was spoken by inhabitants of Scandinavia and their overseas settlemen ...
''tryggð''. Like ''
troth
Troth may refer to:
* An alternate form of truth, especially in the medieval sense
* Troth (surname)
* Troth Yeddha', a landform in the Fairbanks North Star Borough, Alaska
* The Troth, an American Asatru organization
*Troth's Fortune
Troth' ...
'', it is a ''
-th'' nominalisation of the adjective ''true'' (Old English ''tréowe'').
The English word ''
true
True most commonly refers to truth, the state of being in congruence with fact or reality.
True may also refer to:
Places
* True, West Virginia, an unincorporated community in the United States
* True, Wisconsin, a town in the United States
* ...
'' is from Old English (
West Saxon) ''(ge)tríewe,
tréowe'', cognate to
Old Saxon
Old Saxon, also known as Old Low German, was a Germanic language and the earliest recorded form of Low German (spoken nowadays in Northern Germany, the northeastern Netherlands, southern Denmark, the Americas and parts of Eastern Europe). It ...
''(gi)trûui'',
Old High German
Old High German (OHG; german: Althochdeutsch (Ahd.)) is the earliest stage of the German language, conventionally covering the period from around 750 to 1050.
There is no standardised or supra-regional form of German at this period, and Old High ...
''(ga)triuwu'' (
Modern German
New High German (NHG; german: Neuhochdeutsch (Nhd.)) is the term used for the most recent period in the history of the German language, starting in the 17th century. It is a loan translation of the German (). The most important characteristic o ...
''treu'' "faithful"),
Old Norse
Old Norse, Old Nordic, or Old Scandinavian, is a stage of development of North Germanic dialects before their final divergence into separate Nordic languages. Old Norse was spoken by inhabitants of Scandinavia and their overseas settlemen ...
''tryggr'',
Gothic ''triggws'', all from a
Proto-Germanic
Proto-Germanic (abbreviated PGmc; also called Common Germanic) is the reconstructed proto-language of the Germanic branch of the Indo-European languages.
Proto-Germanic eventually developed from pre-Proto-Germanic into three Germanic bran ...
''*trewwj-'' "having
good faith", perhaps ultimately from PIE *dru- "tree", on the notion of "steadfast as an oak" (e.g., Sanskrit ''
dā́ru'' "(piece of) wood").
Old Norse ', "faith, word of honour; religious faith, belief" (archaic English ''
troth
Troth may refer to:
* An alternate form of truth, especially in the medieval sense
* Troth (surname)
* Troth Yeddha', a landform in the Fairbanks North Star Borough, Alaska
* The Troth, an American Asatru organization
*Troth's Fortune
Troth' ...
'' "loyalty,
honesty
Honesty or truthfulness is a facet of moral character that connotes positive and virtuous attributes such as integrity, truthfulness, straightforwardness, including straightforwardness of conduct, along with the absence of lying, cheating, theft ...
, good faith", compare ').
Thus, "truth" involves both the quality of "faithfulness, fidelity, loyalty, sincerity, veracity", and that of "agreement with
fact or
reality
Reality is the sum or aggregate of all that is real or existent within a system, as opposed to that which is only imaginary. The term is also used to refer to the ontological status of things, indicating their existence. In physical terms, r ...
", in Anglo-Saxon expressed by ''
sōþ'' (Modern English ''
sooth'').
All Germanic languages besides English have introduced a terminological distinction between truth "fidelity" and truth "factuality". To express "factuality",
North Germanic
The North Germanic languages make up one of the three branches of the Germanic languages—a sub-family of the Indo-European languages—along with the West Germanic languages and the extinct East Germanic languages. The language group is also r ...
opted for nouns derived from ''sanna'' "to assert, affirm", while continental
West Germanic
The West Germanic languages constitute the largest of the three branches of the Germanic family of languages (the others being the North Germanic and the extinct East Germanic languages). The West Germanic branch is classically subdivided into ...
(German and Dutch) opted for continuations of ''wâra'' "faith, trust, pact" (cognate to Slavic ''věra'' "(religious) faith", but influenced by Latin ''
verus'').
Romance language
The Romance languages, sometimes referred to as Latin languages or Neo-Latin languages, are the various modern languages that evolved from Vulgar Latin. They are the only extant subgroup of the Italic languages in the Indo-European language f ...
s use terms following the Latin ''
veritas
Veritas is the name given to the Roman virtue of truthfulness, which was considered one of the main virtues any good Roman should possess. The Greek goddess of truth is Aletheia (Ancient Greek: ). The German philosopher Martin Heidegger argues ...
'', while the Greek ''
aletheia
''Aletheia'' or Alethia (; grc, ἀλήθεια) is truth or disclosure in philosophy. Originating in Ancient Greek philosophy, the term was later used in the works of 20th-century philosopher Martin Heidegger. Although often translated as " ...
'', Russian ''
pravda
''Pravda'' ( rus, Правда, p=ˈpravdə, a=Ru-правда.ogg, "Truth") is a Russian broadsheet newspaper, and was the official newspaper of the Communist Party of the Soviet Union, when it was one of the most influential papers in the ...
'', South Slavic ''istina'' and Sanskrit ''
sat
The SAT ( ) is a standardized test widely used for college admissions in the United States. Since its debut in 1926, its name and scoring have changed several times; originally called the Scholastic Aptitude Test, it was later called the Schol ...
'' (related to English ''sooth'' and North Germanic ''sanna'') have separate etymological origins.
In some modern contexts, the word "truth" is used to refer to fidelity to an original or standard. It can also be used in the context of being "true to oneself" in the sense of acting with
authenticity.
[
]
Major theories
The question of what is a proper basis for deciding how words, symbols, ideas and beliefs may properly be considered true, whether by a single person or an entire society, is dealt with by the five most prevalent substantive theories of truth listed below. Each presents perspectives that are widely shared by published scholars.Encyclopedia of Philosophy
'' The Encyclopedia of Philosophy'' is one of the major English encyclopedias of philosophy.
The first edition of the encyclopedia was edited by philosopher Paul Edwards (1923–2004), and it was published in two separate printings by Macmil ...
, Supp., "Truth", auth: Michael Williams, pp. 572–73 (Macmillan, 1996)
Theories other than the most prevalent substantive theories are also discussed. More recently developed " deflationary" or "minimalist" theories of truth have emerged as possible alternatives to the most prevalent substantive theories. Minimalist reasoning centres around the notion that the application of a term like ''true'' to a statement does not assert anything significant about it, for instance, anything about its ''nature''. Minimalist reasoning realises ''truth'' as a label utilised in general discourse to express agreement, to stress claims, or to form general assumptions.[
According to a survey of professional philosophers and others on their philosophical views which was carried out in November 2009 (taken by 3226 respondents, including 1803 philosophy faculty members and/or PhDs and 829 philosophy graduate students) 45% of respondents accept or lean towards correspondence theories, 21% accept or lean towards deflationary theories and 14% epistemic theories.
]
Substantive
Correspondence
Correspondence theories emphasize that true beliefs and true statements correspond to the actual state of affairs. This type of theory stresses a relationship between thoughts or statements on one hand, and things or objects on the other. It is a traditional model tracing its origins to ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...
philosophers such as Socrates
Socrates (; ; –399 BC) was a Greek philosopher from Athens who is credited as the founder of Western philosophy and among the first moral philosophers of the ethical tradition of thought. An enigmatic figure, Socrates authored no te ...
, Plato
Plato ( ; grc-gre, Πλάτων ; 428/427 or 424/423 – 348/347 BC) was a Greek philosopher born in Athens during the Classical period in Ancient Greece. He founded the Platonist school of thought and the Academy, the first institution ...
, and Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of ph ...
. This class of theories holds that the truth or the falsity of a representation is determined in principle entirely by how it relates to "things" by whether it accurately describes those "things". A classic example of correspondence theory is the statement by the thirteenth century philosopher and theologian Thomas Aquinas
Thomas Aquinas, OP (; it, Tommaso d'Aquino, lit=Thomas of Aquino; 1225 – 7 March 1274) was an Italian Dominican friar and priest who was an influential philosopher, theologian and jurist in the tradition of scholasticism; he is known wit ...
: "Veritas est adaequatio rei et intellectus
In metaphysics and philosophy of language, the correspondence theory of truth states that the truth or falsity of a statement is determined only by how it relates to the world and whether it accurately describes (i.e., corresponds with) that world ...
" ("Truth is the adequation of things and intellect"), which Aquinas attributed to the ninth century Neoplatonist
Neoplatonism is a strand of Platonic philosophy that emerged in the 3rd century AD against the background of Hellenistic philosophy and religion. The term does not encapsulate a set of ideas as much as a chain of thinkers. But there are some id ...
Isaac Israeli. Aquinas also restated the theory as: "A judgment is said to be true when it conforms to the external reality".
Correspondence theory centres heavily around the assumption that truth is a matter of accurately copying what is known as "objective reality
In philosophy, objectivity is the concept of truth independent from individual subjectivity (bias caused by one's perception, emotions, or imagination). A proposition is considered to have objective truth when its truth conditions are met witho ...
" and then representing it in thoughts, words and other symbols. Many modern theorists have stated that this ideal cannot be achieved without analysing additional factors.[ For example, language plays a role in that all languages have words to represent concepts that are virtually undefined in other languages. The ]German
German(s) may refer to:
* Germany (of or related to)
** Germania (historical use)
* Germans, citizens of Germany, people of German ancestry, or native speakers of the German language
** For citizens of Germany, see also German nationality law
**Ge ...
word ''Zeitgeist
In 18th- and 19th-century German philosophy, a ''Zeitgeist'' () ("spirit of the age") is an invisible agent, force or Daemon dominating the characteristics of a given epoch in world history.
Now, the term is usually associated with Georg W. ...
'' is one such example: one who speaks or understands the language may "know" what it means, but any translation of the word apparently fails to accurately capture its full meaning (this is a problem with many abstract words, especially those derived in agglutinative languages
An agglutinative language is a type of synthetic language with morphology that primarily uses agglutination. Words may contain different morphemes to determine their meanings, but all of these morphemes (including stems and affixes) tend to rem ...
). Thus, some words add an additional parameter to the construction of an accurate truth predicate
In formal theories of truth, a truth predicate is a fundamental concept based on the sentences of a formal language as interpreted logically. That is, it formalizes the concept that is normally expressed by saying that a sentence, statement or idea ...
. Among the philosophers who grappled with this problem is Alfred Tarski
Alfred Tarski (, born Alfred Teitelbaum;School of Mathematics and Statistics, University of St Andrews ''School of Mathematics and Statistics, University of St Andrews''. January 14, 1901 – October 26, 1983) was a Polish-American logician a ...
, whose semantic theory is summarized further on.
Proponents of several of the theories below have gone further to assert that there are yet other issues necessary to the analysis, such as interpersonal power struggles, community interactions, personal biases and other factors involved in deciding what is seen as truth.
Coherence
For coherence theories in general, truth requires a proper fit of elements within a whole system. Very often, though, coherence is taken to imply something more than simple logical consistency; often there is a demand that the propositions in a coherent system lend mutual inferential support to each other. So, for example, the completeness and comprehensiveness of the underlying set of concepts is a critical factor in judging the validity and usefulness of a coherent system. A pervasive tenet of coherence theories is the idea that truth is primarily a property of whole systems of propositions, and can be ascribed to individual propositions only according to their coherence with the whole. Among the assortment of perspectives commonly regarded as coherence theory, theorists differ on the question of whether coherence entails many possible true systems of thought or only a single absolute system.
Some variants of coherence theory are claimed to describe the essential and intrinsic properties of formal system
A formal system is an abstract structure used for inferring theorems from axioms according to a set of rules. These rules, which are used for carrying out the inference of theorems from axioms, are the logical calculus of the formal system.
A form ...
s in logic and mathematics. However, formal reasoners are content to contemplate axiomatically independent and sometimes mutually contradictory systems side by side, for example, the various alternative geometries. On the whole, coherence theories have been rejected for lacking justification in their application to other areas of truth, especially with respect to assertions about the natural world
''Natural World'' is a strand of British wildlife documentary programmes broadcast on BBC Two and BBC Two HD and regarded by the BBC as its flagship natural history series. It is the longest-running documentary in its genre on British televis ...
, empirical data in general, assertions about practical matters of psychology and society, especially when used without support from the other major theories of truth.
Coherence theories distinguish the thought of rationalist philosophers, particularly of Baruch Spinoza, Gottfried Wilhelm Leibniz
Gottfried Wilhelm (von) Leibniz . ( – 14 November 1716) was a German polymath active as a mathematician, philosopher, scientist and diplomat. He is one of the most prominent figures in both the history of philosophy and the history of math ...
, and Georg Wilhelm Friedrich Hegel
Georg Wilhelm Friedrich Hegel (; ; 27 August 1770 – 14 November 1831) was a German philosopher. He is one of the most important figures in German idealism and one of the founding figures of modern Western philosophy. His influence extends ...
, along with the British philosopher F. H. Bradley
Francis Herbert Bradley (30 January 1846 – 18 September 1924) was a British idealist philosopher. His most important work was ''Appearance and Reality'' (1893).
Life
Bradley was born at Clapham, Surrey, England (now part of the Greater ...
. They have found a resurgence also among several proponents of logical positivism, notably Otto Neurath
Otto Karl Wilhelm Neurath (; 10 December 1882 – 22 December 1945) was an Austrian-born philosopher of science, sociologist, and political economist. He was also the inventor of the ISOTYPE method of pictorial statistics and an innovator in mu ...
and Carl Hempel.
Pragmatic
The three most influential forms of the ''pragmatic theory of truth'' were introduced around the turn of the 20th century by Charles Sanders Peirce
Charles Sanders Peirce ( ; September 10, 1839 – April 19, 1914) was an American philosopher, logician, mathematician and scientist who is sometimes known as "the father of pragmatism".
Educated as a chemist and employed as a scientist for t ...
, William James
William James (January 11, 1842 – August 26, 1910) was an American philosopher, historian, and psychologist, and the first educator to offer a psychology course in the United States.
James is considered to be a leading thinker of the lat ...
, and John Dewey. Although there are wide differences in viewpoint among these and other proponents of pragmatic theory, they hold in common that truth is verified and confirmed by the results of putting one's concepts into practice.
Peirce defines truth as follows: "Truth is that concordance of an abstract statement with the ideal limit towards which endless investigation would tend to bring scientific belief, which concordance the abstract statement may possess by virtue of the confession of its inaccuracy and one-sidedness, and this confession is an essential ingredient of truth."[Peirce, C.S. (1901), "Truth and Falsity and Error" (in part), pp. 716–20 in ]James Mark Baldwin
James Mark Baldwin (January 12, 1861, Columbia, South Carolina – November 8, 1934, Paris) was an American philosopher and psychologist who was educated at Princeton under the supervision of Scottish philosopher James McCosh and who was one of ...
, ed., ''Dictionary of Philosophy and Psychology'', v. 2. Peirce's section is entitled "''Logical''", beginning on p. 718, column 1, and ending on p. 720 with the initials "(C.S.P.)", see Google Book
Eprint
Reprinted, '' Collected Papers'' v. 5, pp. 565–73. This statement stresses Peirce's view that ideas of approximation, incompleteness, and partiality, what he describes elsewhere as ''fallibilism
Originally, fallibilism (from Medieval Latin: ''fallibilis'', "liable to err") is the philosophical principle that propositions can be accepted even though they cannot be conclusively proven or justified,Haack, Susan (1979)"Fallibilism and Nece ...
'' and "reference to the future", are essential to a proper conception of truth. Although Peirce uses words like ''concordance'' and ''correspondence'' to describe one aspect of the pragmatic sign relation
A sign relation is the basic construct in the theory of signs, also known as semiotics, as developed by Charles Sanders Peirce.
Anthesis
Thus, if a sunflower, in turning towards the sun, becomes by that very act fully capable, without further ...
, he is also quite explicit in saying that definitions of truth based on mere correspondence are no more than ''nominal'' definitions, which he accords a lower status than ''real'' definitions.
William James
William James (January 11, 1842 – August 26, 1910) was an American philosopher, historian, and psychologist, and the first educator to offer a psychology course in the United States.
James is considered to be a leading thinker of the lat ...
's version of pragmatic theory, while complex, is often summarized by his statement that "the 'true' is only the expedient in our way of thinking, just as the 'right' is only the expedient in our way of behaving."[James, William, ''The Meaning of Truth, A Sequel to 'Pragmatism','' (1909).] By this, James meant that truth is a ''quality'', the value of which is confirmed by its effectiveness when applying concepts to practice (thus, "pragmatic").
John Dewey, less broadly than James but more broadly than Peirce, held that inquiry, whether scientific, technical, sociological, philosophical or cultural, is self-corrective over time ''if'' openly submitted for testing by a community of inquirers in order to clarify, justify, refine and/or refute proposed truths.
Though not widely known, a new variation of the pragmatic theory was defined and wielded successfully from the 20th century forward. Defined and named by William Ernest Hocking
William Ernest Hocking (August 10, 1873 – June 12, 1966) was an American idealist philosopher at Harvard University. He continued the work of his philosophical teacher Josiah Royce (the founder of American idealism) in revising idealism to integ ...
, this variation is known as "negative pragmatism". Essentially, what works may or may not be true, but what fails cannot be true because the truth always works. Richard Feynman
Richard Phillips Feynman (; May 11, 1918 – February 15, 1988) was an American theoretical physicist, known for his work in the path integral formulation of quantum mechanics, the theory of quantum electrodynamics, the physics of the superfl ...
also ascribed to it: "We never are definitely right, we can only be sure we are wrong."[Feynman, The Character of Physical Law, New York: Random House, 1994, .] This approach incorporates many of the ideas from Peirce, James, and Dewey. For Peirce, the idea of "... endless investigation would tend to bring about scientific belief ..." fits negative pragmatism in that a negative pragmatist would never stop testing. As Feynman noted, an idea or theory "... could never be proved right, because tomorrow's experiment might succeed in proving wrong what you thought was right." Similarly, James and Dewey's ideas also ascribe truth to repeated testing which is "self-corrective" over time.
Pragmatism and negative pragmatism are also closely aligned with the coherence theory of truth
Coherence theories of truth characterize truth as a property of whole systems of propositions that can be ascribed to individual propositions only derivatively according to their coherence with the whole. While modern coherence theorists hold that ...
in that any testing should not be isolated but rather incorporate knowledge from all human endeavors and experience. The universe is a whole and integrated system, and testing should acknowledge and account for its diversity. As Feynman said, "... if it disagrees with experiment, it is wrong."
Constructivist
Social constructivism
Social constructivism is a sociological theory of knowledge according to which human development is socially situated and knowledge is constructed through interaction with others.
Like social constructionism, social constructivism states th ...
holds that truth is constructed by social processes, is historically and culturally specific, and that it is in part shaped through the power struggles within a community. Constructivism views all of our knowledge as "constructed," because it does not reflect any external "transcendent" realities (as a pure correspondence theory might hold). Rather, perceptions of truth are viewed as contingent on convention, human perception, and social experience. It is believed by constructivists that representations of physical and biological reality, including race
Race, RACE or "The Race" may refer to:
* Race (biology), an informal taxonomic classification within a species, generally within a sub-species
* Race (human categorization), classification of humans into groups based on physical traits, and/or s ...
, sexuality, and gender
Gender is the range of characteristics pertaining to femininity and masculinity and differentiating between them. Depending on the context, this may include sex-based social structures (i.e. gender roles) and gender identity. Most cultures ...
, are socially constructed.
Giambattista Vico
Giambattista Vico (born Giovan Battista Vico ; ; 23 June 1668 – 23 January 1744) was an Italian philosopher, rhetorician, historian, and jurist during the Italian Enlightenment. He criticized the expansion and development of modern rationali ...
was among the first to claim that history and culture were man-made. Vico's epistemological orientation gathers the most diverse rays and unfolds in one axiom—''verum ipsum factum''—"truth itself is constructed". Hegel and Marx
Karl Heinrich Marx (; 5 May 1818 – 14 March 1883) was a German philosopher, economist, historian, sociologist, political theorist, journalist, critic of political economy, and socialist revolutionary. His best-known titles are the 1848 ...
were among the other early proponents of the premise that truth is, or can be, socially constructed. Marx, like many critical theorists who followed, did not reject the existence of objective truth but rather distinguished between true knowledge and knowledge that has been distorted through power or ideology. For Marx, scientific and true knowledge is "in accordance with the dialectical understanding of history" and ideological knowledge is "an epiphenomenal expression of the relation of material forces in a given economic arrangement".
Consensus
Consensus theory holds that truth is whatever is agreed upon, or in some versions, might come to be agreed upon, by some specified group. Such a group might include all human beings, or a subset thereof consisting of more than one person.
Among the current advocates of consensus theory as a useful accounting of the concept of "truth" is the philosopher Jürgen Habermas. Habermas maintains that truth is what would be agreed upon in an ideal speech situation. Among the current strong critics of consensus theory is the philosopher Nicholas Rescher
Nicholas Rescher (; ; born 15 July 1928) is a German-American philosopher, polymath, and author, who has been a professor of philosophy at the University of Pittsburgh since 1961. He is chairman of the Center for Philosophy of Science and was fo ...
.
Minimalist
Deflationary
Modern developments in the field of philosophy have resulted in the rise of a new thesis: that the term ''truth'' does not denote a real property of sentences or propositions. This thesis is in part a response to the common use of ''truth predicates'' (e.g., that some particular thing "...is true") which was particularly prevalent in philosophical discourse on truth in the first half of the 20th century. From this point of view, to assert that "'2 + 2 = 4' is true" is logically equivalent to asserting that "2 + 2 = 4", and the phrase "is true" is completely dispensable in this and every other context. In common parlance, truth predicates are not commonly heard, and it would be interpreted as an unusual occurrence were someone to utilise a truth predicate in an everyday conversation when asserting that something is true. Newer perspectives that take this discrepancy into account and work with sentence structures that are actually employed in common discourse can be broadly described:
* as ''deflationary'' theories of truth, since they attempt to deflate the presumed importance of the words "true" or ''truth'',
* as ''disquotational'' theories, to draw attention to the disappearance of the quotation marks in cases like the above example, or
* as ''minimalist'' theories of truth.[
Whichever term is used, deflationary theories can be said to hold in common that " e predicate 'true' is an expressive convenience, not the name of a property requiring deep analysis."][ Once we have identified the truth predicate's formal features and utility, deflationists argue, we have said all there is to be said about truth. Among the theoretical concerns of these views is to explain away those special cases where it ''does'' appear that the concept of truth has peculiar and interesting properties. (See, e.g., Semantic paradoxes, and below.)
In addition to highlighting such formal aspects of the predicate "is true", some deflationists point out that the concept enables us to express things that might otherwise require infinitely long sentences. For example, one cannot express confidence in Michael's accuracy by asserting the endless sentence:
:''Michael says, 'snow is white' and snow is white, or he says 'roses are red' and roses are red or he says ... etc.''
This assertion can also be succinctly expressed by saying: ''What Michael says is true''.
]
Performative
Attributed to P. F. Strawson
Peter Frederick Strawson (; 23 November 1919 – 13 February 2006) was an English philosopher. He was the Waynflete Professor of Metaphysical Philosophy at the University of Oxford (Magdalen College) from 1968 to 1987. Before that, he ...
is the performative theory of truth which holds that to say "'Snow is white' is true" is to perform the speech act of signaling one's agreement with the claim that snow is white (much like nodding one's head in agreement). The idea that some statements are more actions than communicative statements is not as odd as it may seem. For example, when a wedding couple says "I do" at the appropriate time in a wedding, they are performing the act of taking the other to be their lawful wedded spouse. They are not ''describing'' themselves as taking the other, but actually ''doing'' so (perhaps the most thorough analysis of such "illocutionary acts" is J. L. Austin
John Langshaw Austin (26 March 1911 – 8 February 1960) was a British philosopher of language and leading proponent of ordinary language philosophy, perhaps best known for developing the theory of speech acts.
Austin pointed out that we u ...
, "How to Do Things With Words
John Langshaw Austin (26 March 1911 – 8 February 1960) was a British philosopher of language and leading proponent of ordinary language philosophy, perhaps best known for developing the theory of speech acts.
Austin pointed out that we u ...
").
Strawson holds that a similar analysis is applicable to all speech acts, not just illocutionary ones: "To say a statement is true is not to make a statement about a statement, but rather to perform the act of agreeing with, accepting, or endorsing a statement. When one says 'It's true that it's raining,' one asserts no more than 'It's raining.' The function of he statement'It's true that...' is to agree with, accept, or endorse the statement that 'it's raining.'"
Redundancy and related
According to the redundancy theory of truth According to the redundancy theory of truth (also known as the disquotational theory of truth), asserting that a statement is true is completely equivalent to asserting the statement itself. For example, asserting the sentence "'Snow is white' is tr ...
, asserting that a statement is true is completely equivalent to asserting the statement itself. For example, making the assertion that " 'Snow is white' is true" is equivalent to asserting "Snow is white". Redundancy theorists infer from this premise that truth is a redundant concept; that is, it is merely a word that is traditionally used in conversation or writing, generally for emphasis, but not a word that actually equates to anything in reality. This theory is commonly attributed to Frank P. Ramsey
Frank Plumpton Ramsey (; 22 February 1903 – 19 January 1930) was a British philosopher, mathematician, and economist who made major contributions to all three fields before his death at the age of 26. He was a close friend of Ludwig Wittgenste ...
, who held that the use of words like ''fact'' and ''truth'' was nothing but a roundabout way of asserting a proposition, and that treating these words as separate problems in isolation from judgment was merely a "linguistic muddle".
A variant of redundancy theory is the disquotational theory which uses a modified form of Tarski's schema
The word schema comes from the Greek word ('), which means ''shape'', or more generally, ''plan''. The plural is ('). In English, both ''schemas'' and ''schemata'' are used as plural forms.
Schema may refer to:
Science and technology
* SCHEMA ...
: To say that '"P" is true' is to say that P. A version of this theory was defended by C. J. F. Williams in his book ''What is Truth?'' Yet another version of deflationism is the prosentential theory of truth, first developed by Dorothy Grover, Joseph Camp, and Nuel Belnap
Nuel Dinsmore Belnap Jr. (; born 1930) is an American logician and philosopher who has made contributions to the philosophy of logic, temporal logic, and structural proof theory. He taught at the University of Pittsburgh from 1963 until his reti ...
as an elaboration of Ramsey's claims. They argue that sentences like "That's true", when said in response to "It's raining", are prosentences, expressions that merely repeat the content of other expressions. In the same way that ''it'' means the same as ''my dog'' in the sentence ''My dog was hungry, so I fed it'', ''That's true'' is supposed to mean the same as ''It's raining''—if one says the latter and another then says the former. These variations do not necessarily follow Ramsey in asserting that truth is ''not'' a property, but rather can be understood to say that, for instance, the assertion "P" may well involve a substantial truth, and the theorists in this case are minimizing only the redundancy or prosentence involved in the statement such as "that's true".[
Deflationary principles do not apply to representations that are not analogous to sentences, and also do not apply to many other things that are commonly judged to be true or otherwise.
]
Philosophical skepticism
Philosophical skepticism
Philosophical skepticism ( UK spelling: scepticism; from Greek σκέψις ''skepsis'', "inquiry") is a family of philosophical views that question the possibility of knowledge. It differs from other forms of skepticism in that it even reject ...
is generally any questioning attitude or doubt
Doubt is a mental state in which the mind remains suspended between two or more contradictory propositions, unable to be certain of any of them.
Doubt on an emotional level is indecision between belief and disbelief. It may involve uncertainty ...
towards one or more items of knowledge
Knowledge can be defined as Descriptive knowledge, awareness of facts or as Procedural knowledge, practical skills, and may also refer to Knowledge by acquaintance, familiarity with objects or situations. Knowledge of facts, also called pro ...
or belief
A belief is an attitude that something is the case, or that some proposition is true. In epistemology, philosophers use the term "belief" to refer to attitudes about the world which can be either true or false. To believe something is to take ...
which ascribe truth to their assertions and propositions. The primary target of philosophical skepticism is epistemology
Epistemology (; ), or the theory of knowledge, is the branch of philosophy concerned with knowledge. Epistemology is considered a major subfield of philosophy, along with other major subfields such as ethics, logic, and metaphysics.
Epis ...
, but it can be applied to any domain, such as the supernatural, morality ( moral skepticism), and religion
Religion is usually defined as a social- cultural system of designated behaviors and practices, morals, beliefs, worldviews, texts, sanctified places, prophecies, ethics, or organizations, that generally relates humanity to supernatural, ...
(skepticism about the existence of God).
Philosophical skepticism comes in various forms. Radical forms of skepticism deny that knowledge or rational belief is possible and urge us to suspend judgment regarding ascription of truth on many or all controversial matters. More moderate forms of skepticism claim only that nothing can be known with certainty, or that we can know little or nothing about the "big questions" in life, such as whether God exists or whether there is an afterlife. Religious skepticism
Religious skepticism is a type of skepticism relating to religion. Religious skeptics question religious authority and are not necessarily anti-religious but skeptical of specific or all religious beliefs and/or practices. Socrates was one of th ...
is "doubt concerning basic religious principles (such as immortality, providence, and revelation)". Scientific skepticism
Scientific skepticism or rational skepticism (also spelled scepticism), sometimes referred to as skeptical inquiry, is a position in which one questions the veracity of claims lacking empirical evidence. In practice, the term most commonly refe ...
concerns testing beliefs for reliability, by subjecting them to systematic investigation using the scientific method
The scientific method is an empirical method for acquiring knowledge that has characterized the development of science since at least the 17th century (with notable practitioners in previous centuries; see the article history of scientific ...
, to discover empirical evidence
Empirical evidence for a proposition is evidence, i.e. what supports or counters this proposition, that is constituted by or accessible to sense experience or experimental procedure. Empirical evidence is of central importance to the sciences ...
for them.
Pluralist
Several of the major theories of truth hold that there is a particular property the having of which makes a belief or proposition true. Pluralist theories of truth assert that there may be more than one property that makes propositions true: ethical propositions might be true by virtue of coherence. Propositions about the physical world might be true by corresponding to the objects and properties they are about.
Some of the pragmatic theories, such as those by Charles Peirce and William James
William James (January 11, 1842 – August 26, 1910) was an American philosopher, historian, and psychologist, and the first educator to offer a psychology course in the United States.
James is considered to be a leading thinker of the lat ...
, included aspects of correspondence, coherence and constructivist theories.[ ]Crispin Wright
Crispin James Garth Wright (; born 21 December 1942) is a British philosopher, who has written on neo-Fregean (neo-logicist) philosophy of mathematics, Wittgenstein's later philosophy, and on issues related to truth, realism, cognitivism, skep ...
argued in his 1992 book ''Truth and Objectivity'' that any predicate which satisfied certain platitudes about truth qualified as a truth predicate. In some discourses, Wright argued, the role of the truth predicate might be played by the notion of superassertibility. Michael Lynch, in a 2009 book ''Truth as One and Many'', argued that we should see truth as a functional property capable of being multiply manifested in distinct properties like correspondence or coherence.
Formal theories
Logic
Logic
Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from premise ...
is concerned with the patterns in reason
Reason is the capacity of consciously applying logic by drawing conclusions from new or existing information, with the aim of seeking the truth. It is closely associated with such characteristically human activities as philosophy, science, ...
that can help tell if a proposition
In logic and linguistics, a proposition is the meaning of a declarative sentence. In philosophy, " meaning" is understood to be a non-linguistic entity which is shared by all sentences with the same meaning. Equivalently, a proposition is the no ...
is true or not. Logicians use formal language
In logic, mathematics, computer science, and linguistics, a formal language consists of words whose letters are taken from an alphabet and are well-formed according to a specific set of rules.
The alphabet of a formal language consists of sy ...
s to express the truths which they are concerned with, and as such there is only truth under some interpretation or truth within some logical system
A formal system is an abstract structure used for inferring theorems from axioms according to a set of rules. These rules, which are used for carrying out the inference of theorems from axioms, are the logical calculus of the formal system.
A form ...
.
A logical truth (also called an analytic truth or a necessary truth) is a statement which is true in all possible worlds or under all possible interpretations, as contrasted to a '' fact'' (also called a '' synthetic claim'' or a '' contingency'') which is only true in this world
In its most general sense, the term "world" refers to the totality of entities, to the whole of reality or to everything that is. The nature of the world has been conceptualized differently in different fields. Some conceptions see the worl ...
as it has historically unfolded. A proposition such as "If p and q, then p" is considered to be a logical truth because of the meaning of the symbols and words
A word is a basic element of language that carries an objective or practical meaning, can be used on its own, and is uninterruptible. Despite the fact that language speakers often have an intuitive grasp of what a word is, there is no conse ...
in it and not because of any fact of any particular world. They are such that they could not be untrue.
Degrees of truth
Truth is the property of being in accord with fact or reality.Merriam-Webster's Online Dictionarytruth 2005 In everyday language, truth is typically ascribed to things that aim to represent reality or otherwise correspond to it, such as belie ...
in logic may be represented using two or more discrete values, as with bivalent logic
In logic, the semantic principle (or law) of bivalence states that every declarative sentence expressing a proposition (of a theory under inspection) has exactly one truth value, either true or false. A logic satisfying this principle is calle ...
(or binary logic), three-valued logic
In logic, a three-valued logic (also trinary logic, trivalent, ternary, or trilean, sometimes abbreviated 3VL) is any of several many-valued logic systems in which there are three truth values indicating ''true'', ''false'' and some indeterminate ...
, and other forms of finite-valued logic In logic, a finite-valued logic (also finitely many-valued logic) is a propositional calculus in which truth values are discrete. Traditionally, in Aristotle's logic, the bivalent logic, also known as binary logic was the norm, as the law of the ...
. Truth in logic can be represented using numbers comprising a continuous
Continuity or continuous may refer to:
Mathematics
* Continuity (mathematics), the opposing concept to discreteness; common examples include
** Continuous probability distribution or random variable in probability and statistics
** Continuous ...
range, typically between 0 and 1, as with fuzzy logic and other forms of infinite-valued logic. In general, the concept of representing truth using more than two values is known as many-valued logic
Many-valued logic (also multi- or multiple-valued logic) refers to a propositional calculus in which there are more than two truth values. Traditionally, in Aristotle's logical calculus, there were only two possible values (i.e., "true" and "false ...
.
Mathematics
There are two main approaches to truth in mathematics. They are the '' model theory of truth'' and the '' proof theory of truth''.
Historically, with the nineteenth century development of Boolean algebra
In mathematics and mathematical logic, Boolean algebra is a branch of algebra. It differs from elementary algebra in two ways. First, the values of the variables are the truth values ''true'' and ''false'', usually denoted 1 and 0, whereas i ...
mathematical models of logic began to treat "truth", also represented as "T" or "1", as an arbitrary constant. "Falsity" is also an arbitrary constant, which can be represented as "F" or "0". In propositional logic
Propositional calculus is a branch of logic. It is also called propositional logic, statement logic, sentential calculus, sentential logic, or sometimes zeroth-order logic. It deals with propositions (which can be true or false) and relations b ...
, these symbols can be manipulated according to a set of axioms
An axiom, postulate, or assumption is a statement that is taken to be true, to serve as a premise or starting point for further reasoning and arguments. The word comes from the Ancient Greek word (), meaning 'that which is thought worthy or f ...
and rules of inference
In the philosophy of logic, a rule of inference, inference rule or transformation rule is a logical form consisting of a function which takes premises, analyzes their syntax, and returns a conclusion (or conclusions). For example, the rule of ...
, often given in the form of truth table
A truth table is a mathematical table used in logic—specifically in connection with Boolean algebra, boolean functions, and propositional calculus—which sets out the functional values of logical expressions on each of their functional argumen ...
s.
In addition, from at least the time of Hilbert's program
In mathematics, Hilbert's program, formulated by German mathematician David Hilbert in the early part of the 20th century, was a proposed solution to the foundational crisis of mathematics, when early attempts to clarify the foundations of mathema ...
at the turn of the twentieth century to the proof of Gödel's incompleteness theorems and the development of the Church–Turing thesis in the early part of that century, true statements in mathematics were generally assumed to be those statements that are provable in a formal axiomatic system.
The works of Kurt Gödel, Alan Turing
Alan Mathison Turing (; 23 June 1912 – 7 June 1954) was an English mathematician, computer scientist, logician, cryptanalyst, philosopher, and theoretical biologist. Turing was highly influential in the development of theoretical co ...
, and others shook this assumption, with the development of statements that are true but cannot be proven within the system. Two examples of the latter can be found in Hilbert's problems. Work on Hilbert's 10th problem led in the late twentieth century to the construction of specific Diophantine equations
In mathematics, a Diophantine equation is an equation, typically a polynomial equation in two or more unknowns with integer coefficients, such that the only solutions of interest are the integer ones. A linear Diophantine equation equates to a c ...
for which it is undecidable whether they have a solution, or even if they do, whether they have a finite or infinite number of solutions. More fundamentally, Hilbert's first problem was on the continuum hypothesis
In mathematics, the continuum hypothesis (abbreviated CH) is a hypothesis about the possible sizes of infinite sets. It states that
or equivalently, that
In Zermelo–Fraenkel set theory with the axiom of choice (ZFC), this is equivalent to ...
. Gödel and Paul Cohen
Paul Joseph Cohen (April 2, 1934 – March 23, 2007) was an American mathematician. He is best known for his proofs that the continuum hypothesis and the axiom of choice are independent from Zermelo–Fraenkel set theory, for which he was award ...
showed that this hypothesis cannot be proved or disproved using the standard axioms of set theory
Set theory is the branch of mathematical logic that studies sets, which can be informally described as collections of objects. Although objects of any kind can be collected into a set, set theory, as a branch of mathematics, is mostly conce ...
. In the view of some, then, it is equally reasonable to take either the continuum hypothesis or its negation as a new axiom.
Gödel thought that the ability to perceive the truth of a mathematical or logical proposition is a matter of intuition
Intuition is the ability to acquire knowledge without recourse to conscious reasoning. Different fields use the word "intuition" in very different ways, including but not limited to: direct access to unconscious knowledge; unconscious cognition; ...
, an ability he admitted could be ultimately beyond the scope of a formal theory of logic or mathematics and perhaps best considered in the realm of human comprehension and communication, but commented:
Tarski's semantics
The semantic theory of truth
A semantic theory of truth is a theory of truth in the philosophy of language which holds that truth is a property of sentences.
Origin
The semantic conception of truth, which is related in different ways to both the correspondence and deflati ...
has as its general case for a given language:
:'P' is true if and only if P
where 'P' refers to the sentence (the sentence's name), and P is just the sentence itself.
Tarski's theory of truth (named after Alfred Tarski
Alfred Tarski (, born Alfred Teitelbaum;School of Mathematics and Statistics, University of St Andrews ''School of Mathematics and Statistics, University of St Andrews''. January 14, 1901 – October 26, 1983) was a Polish-American logician a ...
) was developed for formal languages, such as formal logic
Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from premis ...
. Here he restricted it in this way: no language could contain its own truth predicate, that is, the expression ''is true'' could only apply to sentences in some other language. The latter he called an ''object language'', the language being talked about. (It may, in turn, have a truth predicate that can be applied to sentences in still another language.) The reason for his restriction was that languages that contain their own truth predicate will contain paradoxical
A paradox is a logically self-contradictory statement or a statement that runs contrary to one's expectation. It is a statement that, despite apparently valid reasoning from true premises, leads to a seemingly self-contradictory or a logically u ...
sentences such as, "This sentence is not true". As a result, Tarski held that the semantic theory could not be applied to any natural language, such as English, because they contain their own truth predicates. Donald Davidson used it as the foundation of his truth-conditional semantics Truth-conditional semantics is an approach to semantics of natural language that sees meaning (or at least the meaning of assertions) as being the same as, or reducible to, their truth conditions. This approach to semantics is principally associate ...
and linked it to radical interpretation Radical interpretation is interpretation of a speaker, including attributing beliefs and desires to them and meanings to their words, from scratch—that is, without relying on translators, dictionaries, or specific prior knowledge of their mental s ...
in a form of coherentism
In philosophical epistemology, there are two types of coherentism: the coherence theory of truth; and the coherence theory of justification (also known as epistemic coherentism).
Coherent truth is divided between an anthropological approach, wh ...
.
Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell, (18 May 1872 – 2 February 1970) was a British mathematician, philosopher, logician, and public intellectual. He had a considerable influence on mathematics, logic, set theory, linguistics, ...
is credited with noticing the existence of such paradoxes even in the best symbolic formations of mathematics in his day, in particular the paradox that came to be named after him, Russell's paradox
In mathematical logic, Russell's paradox (also known as Russell's antinomy) is a set-theoretic paradox discovered by the British philosopher and mathematician Bertrand Russell in 1901. Russell's paradox shows that every set theory that contains ...
. Russell and Whitehead attempted to solve these problems in ''Principia Mathematica
The ''Principia Mathematica'' (often abbreviated ''PM'') is a three-volume work on the foundations of mathematics written by mathematician–philosophers Alfred North Whitehead and Bertrand Russell and published in 1910, 1912, and 1913. ...
'' by putting statements into a hierarchy of types
Type may refer to:
Science and technology Computing
* Typing, producing text via a keyboard, typewriter, etc.
* Data type
In computer science and computer programming, a data type (or simply type) is a set of possible values and a set of allo ...
, wherein a statement cannot refer to itself, but only to statements lower in the hierarchy. This in turn led to new orders of difficulty regarding the precise natures of types and the structures of conceptually possible type system
In computer programming, a type system is a logical system comprising a set of rules that assigns a property called a type to every "term" (a word, phrase, or other set of symbols). Usually the terms are various constructs of a computer progr ...
s that have yet to be resolved to this day.
Kripke's semantics
Kripke's theory of truth
A semantic theory of truth is a theory of truth in the philosophy of language which holds that truth is a property of sentences.
Origin
The semantic conception of truth, which is related in different ways to both the correspondence and deflatio ...
(named after Saul Kripke
Saul Aaron Kripke (; November 13, 1940 – September 15, 2022) was an American philosopher and logician in the analytic tradition. He was a Distinguished Professor of Philosophy at the Graduate Center of the City University of New York and em ...
) contends that a natural language can in fact contain its own truth predicate without giving rise to contradiction. He showed how to construct one as follows:
* Beginning with a subset of sentences of a natural language that contains no occurrences of the expression "is true" (or "is false"). So ''The barn is big'' is included in the subset, but not "''The barn is big'' is true", nor problematic sentences such as "''This sentence'' is false".
* Defining truth just for the sentences in that subset.
* Extending the definition of truth to include sentences that predicate truth or falsity of one of the original subset of sentences. So "''The barn is big'' is true" is now included, but not either "''This sentence'' is false" nor "'''The barn is big'' is true' is true".
* Defining truth for all sentences that predicate truth or falsity of a member of the second set. Imagine this process repeated infinitely, so that truth is defined for ''The barn is big''; then for "''The barn is big'' is true"; then for "'''The barn is big'' is true' is true", and so on.
Truth never gets defined for sentences like ''This sentence is false'', since it was not in the original subset and does not predicate truth of any sentence in the original or any subsequent set. In Kripke's terms, these are "ungrounded." Since these sentences are never assigned either truth or falsehood even if the process is carried out infinitely, Kripke's theory implies that some sentences are neither true nor false. This contradicts the principle of bivalence
In logic, the semantic principle (or law) of bivalence states that every declarative sentence expressing a proposition (of a theory under inspection) has exactly one truth value, either true or false. A logic satisfying this principle is called ...
: every sentence must be either true or false. Since this principle is a key premise in deriving the liar paradox
In philosophy and logic, the classical liar paradox or liar's paradox or antinomy of the liar is the statement of a liar that they are lying: for instance, declaring that "I am lying". If the liar is indeed lying, then the liar is telling the truth ...
, the paradox is dissolved.
However, it has been shown by Gödel that self-reference cannot be avoided naively, since propositions about seemingly unrelated objects can have an informal self-referential meaning; in Gödel's work, these objects are integer numbers, and they have an informal meaning regarding propositions. In fact, this idea — manifested by the diagonal lemma
In mathematical logic, the diagonal lemma (also known as diagonalization lemma, self-reference lemma or fixed point theorem) establishes the existence of self-referential sentences in certain formal theories of the natural numbers—specificall ...
—is the basis for Tarski's theorem that truth cannot be consistently defined.
It has thus been claimed that Kripke's system indeed leads to contradiction: while its truth predicate is only partial, it does give truth value (true/false) to propositions such as the one built in Tarski's proof, and is therefore inconsistent. While there is still a debate on whether Tarski's proof can be implemented to every similar partial truth system, none have been shown to be consistent by acceptable methods used in mathematical logic
Mathematical logic is the study of formal logic within mathematics. Major subareas include model theory, proof theory, set theory, and recursion theory. Research in mathematical logic commonly addresses the mathematical properties of formal ...
.
Kripke's semantics are related to the use of topoi and other concepts from category theory in the study of mathematical logic
Mathematical logic is the study of formal logic within mathematics. Major subareas include model theory, proof theory, set theory, and recursion theory. Research in mathematical logic commonly addresses the mathematical properties of formal ...
. They provide a choice of formal semantics for intuitionistic logic
Intuitionistic logic, sometimes more generally called constructive logic, refers to systems of symbolic logic that differ from the systems used for classical logic by more closely mirroring the notion of constructive proof. In particular, systems ...
.
Folk beliefs
The truth predicate
In formal theories of truth, a truth predicate is a fundamental concept based on the sentences of a formal language as interpreted logically. That is, it formalizes the concept that is normally expressed by saying that a sentence, statement or idea ...
"''P'' is true" has great practical value in human language, allowing ''efficient'' endorsement or impeaching of claims made by others, to emphasize the truth or falsity of a statement, or to enable various indirect ( Gricean) conversational implications. Individuals or societies will sometime punish "false" statements to deter falsehoods; the oldest surviving law text, the Code of Ur-Nammu, lists penalties for false accusations of sorcery or adultery, as well as for committing perjury
Perjury (also known as foreswearing) is the intentional act of swearing a false oath or falsifying an affirmation to tell the truth, whether spoken or in writing, concerning matters material to an official proceeding."Perjury The act or an inst ...
in court. Even four-year-old children can pass simple "false belief
In psychology, theory of mind refers to the capacity to understand other people by ascribing mental states to them (that is, surmising what is happening in their mind). This includes the knowledge that others' mental states may be different fro ...
" tests and successfully assess that another individual's belief diverges from reality in a specific way; by adulthood there are strong implicit intuitions about "truth" that form a "folk theory" of truth. These intuitions include:
* Capture (''T''-in): If ''P'', then ''P'' is true
* Release (''T''-out): If ''P'' is true, then ''P''
* Noncontradiction: A statement can not be both true and false
* Normativity: It is usually good to believe what is true
* False beliefs: The notion that believing a statement does not necessarily make it true
Like many folk theories, the folk theory of truth is useful in everyday life but, upon deep analysis, turns out to be technically self-contradictory; in particular, any formal system
A formal system is an abstract structure used for inferring theorems from axioms according to a set of rules. These rules, which are used for carrying out the inference of theorems from axioms, are the logical calculus of the formal system.
A form ...
that fully obeys "capture and release" semantics for truth (also known as the ''T-schema
The T-schema ("truth schema", not to be confused with " Convention T") is used to check if an inductive definition of truth is valid, which lies at the heart of any realisation of Alfred Tarski's semantic theory of truth. Some authors refer to it ...
''), and that also respects classical logic, is provably inconsistent
In classical deductive logic, a consistent theory is one that does not lead to a logical contradiction. The lack of contradiction can be defined in either semantic or syntactic terms. The semantic definition states that a theory is consistent ...
and succumbs to the liar paradox
In philosophy and logic, the classical liar paradox or liar's paradox or antinomy of the liar is the statement of a liar that they are lying: for instance, declaring that "I am lying". If the liar is indeed lying, then the liar is telling the truth ...
or to a similar contradiction.
Notable views
Ancient Greek philosophy
Socrates
Socrates (; ; –399 BC) was a Greek philosopher from Athens who is credited as the founder of Western philosophy and among the first moral philosophers of the ethical tradition of thought. An enigmatic figure, Socrates authored no te ...
', Plato
Plato ( ; grc-gre, Πλάτων ; 428/427 or 424/423 – 348/347 BC) was a Greek philosopher born in Athens during the Classical period in Ancient Greece. He founded the Platonist school of thought and the Academy, the first institution ...
's and Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of ph ...
's ideas about truth are seen by some as consistent with correspondence theory
In metaphysics and philosophy of language, the correspondence theory of truth states that the truth or falsity of a statement is determined only by how it relates to the world and whether it accurately describes (i.e., corresponds with) that world ...
. In his ''Metaphysics
Metaphysics is the branch of philosophy that studies the fundamental nature of reality, the first principles of being, identity and change, space and time, causality, necessity, and possibility. It includes questions about the nature of conscio ...
'', Aristotle stated: "To say of what is that it is not, or of what is not that it is, is false, while to say of what is that it is, and of what is not that it is not, is true".[David, Marion (2005)]
"Correspondence Theory of Truth"
in Stanford Encyclopedia of Philosophy The Stanford Encyclopedia of Philosophy proceeds to say of Aristotle:
..Aristotle sounds much more like a genuine correspondence theorist in the ''Categories'' (12b11, 14b14), where he talks of "underlying things" that make statements true and implies that these "things" (pragmata) are logically structured situations or facts (viz., his sitting, his not sitting). Most influential is his claim in ''De Interpretatione'' (16a3) that thoughts are "likenesses" (homoiosis) of things. Although he nowhere defines truth in terms of a thought's likeness to a thing or fact, it is clear that such a definition would fit well into his overall philosophy of mind. ..ref name=StanfordCorr/>
Similar statements can also be found in Plato's dialogues ('' Cratylus'' 385b2, ''Sophist
A sophist ( el, σοφιστής, sophistes) was a teacher in ancient Greece in the fifth and fourth centuries BC. Sophists specialized in one or more subject areas, such as philosophy, rhetoric, music, athletics, and mathematics. They taught ' ...
'' 263b).[
Some Greek philosophers maintained that truth was either not accessible to mortals, or of greatly limited accessibility, forming early ]philosophical skepticism
Philosophical skepticism ( UK spelling: scepticism; from Greek σκέψις ''skepsis'', "inquiry") is a family of philosophical views that question the possibility of knowledge. It differs from other forms of skepticism in that it even reject ...
. Among these were Xenophanes
Xenophanes of Colophon (; grc, Ξενοφάνης ὁ Κολοφώνιος ; c. 570 – c. 478 BC) was a Greek philosopher, theologian, poet, and critic of Homer from Ionia who travelled throughout the Greek-speaking world in early Classical ...
, Democritus
Democritus (; el, Δημόκριτος, ''Dēmókritos'', meaning "chosen of the people"; – ) was an Ancient Greek pre-Socratic philosopher from Abdera, primarily remembered today for his formulation of an atomic theory of the universe. No ...
, and Pyrrho, the founder of Pyrrhonism, who argued that there was no criterion of truth.
The Epicureans
Epicureanism is a system of philosophy founded around 307 BC based upon the teachings of the ancient Greek philosopher Epicurus. Epicureanism was originally a challenge to Platonism. Later its main opponent became Stoicism.
Few writings by ...
believed that all sense perceptions were true, and that errors arise in how we judge those perceptions.
The Stoics conceived truth as accessible from impressions via cognitive grasping.
Medieval philosophy
Avicenna (980–1037)
In early Islamic philosophy, Avicenna (Ibn Sina) defined truth in his work Kitab Al-Shifa ''The Book of Healing
''The Book of Healing'' (; ; also known as ) is a scientific and philosophical encyclopedia written by Abu Ali ibn Sīna (aka Avicenna) from medieval Persia, near Bukhara in Maverounnahr. He most likely began to compose the book in 1014, comp ...
'', Book I, Chapter 8, as:
Avicenna elaborated on his definition of truth later in Book VIII, Chapter 6:
However, this definition is merely a rendering of the medieval
In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire ...
Latin translation of the work by Simone van Riet. A modern translation of the original Arabic text states:
Aquinas (1225–1274)
Reevaluating Avicenna, and also Augustine and Aristotle, Thomas Aquinas
Thomas Aquinas, OP (; it, Tommaso d'Aquino, lit=Thomas of Aquino; 1225 – 7 March 1274) was an Italian Dominican friar and priest who was an influential philosopher, theologian and jurist in the tradition of scholasticism; he is known wit ...
stated in his ''Disputed Questions on Truth'':
Thus, for Aquinas, the truth of the human intellect (logical truth) is based on the truth in things (ontological truth). Following this, he wrote an elegant re-statement of Aristotle's view in hi
Summa I.16.1
Aquinas also said that real things participate in the act of being of the Creator God who is Subsistent Being, Intelligence, and Truth. Thus, these beings possess the light of intelligibility and are knowable. These things (beings; reality
Reality is the sum or aggregate of all that is real or existent within a system, as opposed to that which is only imaginary. The term is also used to refer to the ontological status of things, indicating their existence. In physical terms, r ...
) are the foundation of the truth that is found in the human mind, when it acquires knowledge of things, first through the sense
A sense is a biological system used by an organism for sensation, the process of gathering information about the world through the detection of stimuli. (For example, in the human body, the brain which is part of the central nervous system re ...
s, then through the understanding
Understanding is a psychological process related to an abstract or physical object, such as a person, situation, or message whereby one is able to use concepts to model that object.
Understanding is a relation between the knower and an object ...
and the judgement
Judgement (or US spelling judgment) is also known as ''adjudication'', which means the evaluation of evidence to make a decision. Judgement is also the ability to make considered decisions. The term has at least five distinct uses. Aristotle s ...
done by reason
Reason is the capacity of consciously applying logic by drawing conclusions from new or existing information, with the aim of seeking the truth. It is closely associated with such characteristically human activities as philosophy, science, ...
. For Aquinas, human intelligence
Intelligence has been defined in many ways: the capacity for abstraction, logic, understanding, self-awareness, learning, emotional knowledge, reasoning, planning, creativity, critical thinking, and problem-solving. More generally, it can be des ...
("intus", within and "legere", to read) has the capability to reach the essence
Essence ( la, essentia) is a polysemic term, used in philosophy and theology as a designation for the property or set of properties that make an entity or substance what it fundamentally is, and which it has by necessity, and without which it ...
and existence
Existence is the ability of an entity to interact with reality. In philosophy, it refers to the ontological property of being.
Etymology
The term ''existence'' comes from Old French ''existence'', from Medieval Latin ''existentia/exsistentia' ...
of things because it has a non-material, spiritual element, although some moral, educational, and other elements might interfere with its capability.
Changing concepts of truth in the Middle Ages
Richard Firth Green
Richard Firth Green is a Canadian scholar who specializes in Middle English literature. He is a Humanities Distinguished Professor of English Emeritus at Ohio State University and author of three monographs on the social life, law, and literature o ...
examined the concept of truth in the later Middle Ages in his ''A Crisis of Truth'', and concludes that roughly during the reign of Richard II of England the very meaning of the concept changes. The idea of the oath, which was so much part and parcel of for instance Romance literature, changes from a subjective concept to a more objective one (in Derek Pearsall
Derek Albert Pearsall (1931–2021) was a prominent medievalist and Chaucerian who wrote and published widely on Chaucer, Langland, Gower, manuscript studies, and medieval history and culture.
He was the co-director, Emeritus, Centre for Medi ...
's summary). Whereas truth (the "trouthe" of ''Sir Gawain and the Green Knight
''Sir Gawain and the Green Knight'' is a late 14th-century chivalric romance in Middle English. The author is unknown; the title was given centuries later. It is one of the best-known Arthurian stories, with its plot combining two types of ...
'') was first "an ethical truth in which truth is understood to reside in persons", in Ricardian England it "transforms...into a political truth in which truth is understood to reside in documents".
Modern philosophy
Kant (1724–1804)
Immanuel Kant
Immanuel Kant (, , ; 22 April 1724 – 12 February 1804) was a German philosopher and one of the central Enlightenment thinkers. Born in Königsberg, Kant's comprehensive and systematic works in epistemology, metaphysics, ethics, and ...
endorses a definition of truth along the lines of the correspondence theory of truth.[ Kant writes in the '' Critique of Pure Reason'': "The nominal definition of truth, namely that it is the agreement of cognition with its object, is here granted and presupposed".][Kant, Immanuel (1781/1787), '' Critique of Pure Reason''. Translated and edited by Paul Guyer and Allen W. Wood (Cambridge: Cambridge University Press, 1998), A58/B82.] However, Kant denies that this correspondence definition of truth provides us with a test or criterion to establish which judgements are true. Kant states in his logic lectures:
..Truth, it is said, consists in the agreement of cognition with its object. In consequence of this mere nominal definition, my cognition, to count as true, is supposed to agree with its object. Now I can compare the object with my cognition, however, only ''by cognizing it''. Hence my cognition is supposed to confirm itself, which is far short of being sufficient for truth. For since the object is outside me, the cognition in me, all I can ever pass judgement on is whether my cognition of the object agrees with my cognition of the object.
The ancients called such a circle in explanation a ''diallelon''. And actually the logicians were always reproached with this mistake by the sceptics, who observed that with this definition of truth it is just as when someone makes a statement before a court and in doing so appeals to a witness with whom no one is acquainted, but who wants to establish his credibility by maintaining that the one who called him as witness is an honest man. The accusation was grounded, too. Only the solution of the indicated problem is impossible without qualification and for every man. ..ref name = "Kant-1801">Kant, Immanuel (1801), ''The Jäsche Logic'', in ''Lectures on Logic''. Translated and edited by J. Michael Young (Cambridge: Cambridge University Press, 1992), pp. 557–58.
This passage makes use of his distinction between nominal and real definitions. A nominal definition explains the meaning of a linguistic expression. A real definition describes the essence of certain objects and enables us to determine whether any given item falls within the definition.[Alberto Vanzo, "Kant on the Nominal Definition of Truth", ''Kant-Studien'', 101 (2010), pp. 147–66.] Kant holds that the definition of truth is merely nominal and, therefore, we cannot employ it to establish which judgements are true. According to Kant, the ancient skeptics were critical of the logicians for holding that, by means of a merely nominal definition of truth, they can establish which judgements are true. They were trying to do something that is "impossible without qualification and for every man".
Hegel (1770–1831)
Georg Hegel
Georg may refer to:
* ''Georg'' (film), 1997
*Georg (musical), Estonian musical
* Georg (given name)
* Georg (surname) George is a surname of Irish, English, Welsh, South Indian Christian, Middle Eastern Christian (usually Lebanese), French, or ...
distanced his philosophy from psychology by presenting truth as being an external self-moving object instead of being related to inner, subjective thoughts. Hegel's truth is analogous to the mechanics
Mechanics (from Ancient Greek: μηχανική, ''mēkhanikḗ'', "of machines") is the area of mathematics and physics concerned with the relationships between force, matter, and motion among physical objects. Forces applied to object ...
of a material body in motion under the influence of its own inner force. "Truth is its own self-movement within itself." Teleological truth moves itself in the three-step form of dialectical triplicity toward the final goal of perfect, final, absolute truth. According to Hegel, the progression of philosophical truth is a resolution of past oppositions into increasingly more accurate approximations of absolute truth. Chalybäus used the terms "thesis
A thesis ( : theses), or dissertation (abbreviated diss.), is a document submitted in support of candidature for an academic degree or professional qualification presenting the author's research and findings.International Standard ISO 7144: ...
", " antithesis", and " synthesis" to describe Hegel's dialectical triplicity. The "thesis" consists of an incomplete historical movement. To resolve the incompletion, an "antithesis" occurs which opposes the "thesis." In turn, the "synthesis" appears when the "thesis" and "antithesis" become reconciled
''Put Your Hands Down'' is the debut studio album of Penal Colony, released in February 1994 by Cleopatra Records.
Reception
''Factsheet Five'' compared the music of ''Put Your Hands Down'' favorably to Hate Dept. and described Penal Colony as b ...
and a higher level of truth is obtained. This "synthesis" thereby becomes a "thesis," which will again necessitate an "antithesis," requiring a new "synthesis" until a final state is reached as the result of reason's historical movement. History is the Absolute Spirit moving toward a goal. This historical progression will finally conclude itself when the Absolute Spirit understands its own infinite self at the very end of history. Absolute Spirit will then be the complete expression of an infinite God
In monotheistic thought, God is usually viewed as the supreme being, creator, and principal object of faith. Swinburne, R.G. "God" in Honderich, Ted. (ed)''The Oxford Companion to Philosophy'', Oxford University Press, 1995. God is typically ...
.
Schopenhauer (1788–1860)
For Arthur Schopenhauer, a judgment
Judgement (or US spelling judgment) is also known as ''adjudication'', which means the evaluation of evidence to make a decision. Judgement is also the ability to make considered decisions. The term has at least five distinct uses. Aristotle s ...
is a combination or separation of two or more concept
Concepts are defined as abstract ideas. They are understood to be the fundamental building blocks of the concept behind principles, thoughts and beliefs.
They play an important role in all aspects of cognition. As such, concepts are studied by ...
s. If a judgment is to be an expression of knowledge
Knowledge can be defined as Descriptive knowledge, awareness of facts or as Procedural knowledge, practical skills, and may also refer to Knowledge by acquaintance, familiarity with objects or situations. Knowledge of facts, also called pro ...
, it must have a sufficient reason or ground by which the judgment could be called true. ''Truth is the reference of a judgment to something different from itself which is its sufficient reason (ground)''. Judgments can have material, formal, transcendental, or metalogical truth. A judgment has ''material'' truth if its concepts are based on intuitive perceptions that are generated from sensations. If a judgment has its reason (ground) in another judgment, its truth is called logical or ''formal''. If a judgment, of, for example, pure mathematics or pure science, is based on the forms (space, time, causality) of intuitive, empirical knowledge, then the judgment has ''transcendental'' truth.
Kierkegaard (1813–1855)
When Søren Kierkegaard, as his character ''Johannes Climacus'', ends his writings: ''My thesis was, subjectivity, heartfelt is the truth'', he does not advocate for subjectivism
Subjectivism is the doctrine that "our own mental activity is the only unquestionable fact of our experience", instead of shared or communal, and that there is no external or objective truth.
The success of this position is historically attribute ...
in its extreme form (the theory that something is true simply because one believes it to be so), but rather that the objective approach to matters of personal truth cannot shed any light upon that which is most essential to a person's life. Objective truths are concerned with the facts of a person's being, while subjective truths are concerned with a person's way of being. Kierkegaard agrees that objective truths for the study of subjects like mathematics, science, and history are relevant and necessary, but argues that objective truths do not shed any light on a person's inner relationship to existence. At best, these truths can only provide a severely narrowed perspective that has little to do with one's actual experience of life.
While objective truths are final and static, subjective truths are continuing and dynamic. The truth of one's existence is a living, inward, and subjective experience that is always in the process of becoming. The values, morals, and spiritual approaches a person adopts, while not denying the existence of objective truths of those beliefs, can only become truly known when they have been inwardly appropriated through subjective experience. Thus, Kierkegaard criticizes all systematic philosophies which attempt to know life or the truth of existence via theories and objective knowledge about reality. As Kierkegaard claims, human truth is something that is continually occurring, and a human being cannot find truth separate from the subjective experience of one's own existing, defined by the values and fundamental essence that consist of one's way of life.
Nietzsche (1844–1900)
Friedrich Nietzsche
Friedrich Wilhelm Nietzsche (; or ; 15 October 1844 – 25 August 1900) was a German philosopher, prose poet, cultural critic, philologist, and composer whose work has exerted a profound influence on contemporary philosophy. He began his ...
believed the search for truth, or 'the will to truth', was a consequence of the ''will to power
The will to power (german: der Wille zur Macht) is a concept in the philosophy of Friedrich Nietzsche. The will to power describes what Nietzsche may have believed to be the main driving force in humans. However, the concept was never systemati ...
'' of philosophers. He thought that truth should be used as long as it promoted life and the ''will to power'', and he thought untruth was better than truth if it had this life enhancement as a consequence. As he wrote in ''Beyond Good and Evil
''Beyond Good and Evil: Prelude to a Philosophy of the Future'' (german: Jenseits von Gut und Böse: Vorspiel einer Philosophie der Zukunft) is a book by philosopher Friedrich Nietzsche that covers ideas in his previous work ''Thus Spoke Zarathu ...
'', "The falseness of a judgment is to us not necessarily an objection to a judgment... The question is to what extent it is life-advancing, life-preserving, species-preserving, perhaps even species-breeding..." (aphorism 4). He proposed the ''will to power'' as a truth only because, according to him, it was the most life-affirming and sincere perspective one could have.
Robert Wicks discusses Nietzsche's basic view of truth as follows:
..Some scholars regard Nietzsche's 1873 unpublished essay, "On Truth and Lies in a Nonmoral Sense" ("Über Wahrheit und Lüge im außermoralischen Sinn") as a keystone in his thought. In this essay, Nietzsche rejects the idea of universal constants, and claims that what we call "truth" is only "a mobile army of metaphors, metonyms, and anthropomorphisms." His view at this time is that arbitrariness completely prevails within human experience: concepts originate via the very artistic transference of nerve stimuli into images; "truth" is nothing more than the invention of fixed conventions for merely practical purposes, especially those of repose, security and consistence. ../blockquote>
Separately Nietzsche suggested that an ancient, metaphysical belief in the divinity of Truth lies at the heart of and has served as the foundation for the entire subsequent Western intellectual tradition: "But you will have gathered what I am getting at, namely, that it is still a metaphysical faith on which our faith in science rests—that even we knowers of today, we godless anti-metaphysicians still take ''our'' fire too, from the flame lit by the thousand-year old faith, the Christian faith which was also Plato's faith, that God is Truth; that Truth is 'Divine'..."
Heidegger (1889–1976)
Other philosophers take this common meaning to be secondary and derivative. According to Martin Heidegger
Martin Heidegger (; ; 26 September 188926 May 1976) was a German philosopher who is best known for contributions to phenomenology, hermeneutics, and existentialism. He is among the most important and influential philosophers of the 20th ce ...
, the original meaning and essence
Essence ( la, essentia) is a polysemic term, used in philosophy and theology as a designation for the property or set of properties that make an entity or substance what it fundamentally is, and which it has by necessity, and without which it ...
of truth in Ancient Greece
Ancient Greece ( el, Ἑλλάς, Hellás) was a northeastern Mediterranean Sea, Mediterranean civilization, existing from the Greek Dark Ages of the 12th–9th centuries BC to the end of Classical Antiquity, classical antiquity ( AD 600), th ...
was unconcealment, or the revealing or bringing of what was previously hidden into the open, as indicated by the original Greek term for truth, ''aletheia
''Aletheia'' or Alethia (; grc, ἀλήθεια) is truth or disclosure in philosophy. Originating in Ancient Greek philosophy, the term was later used in the works of 20th-century philosopher Martin Heidegger. Although often translated as " ...
''. On this view, the conception of truth as correctness is a later derivation from the concept's original essence, a development Heidegger traces to the Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
term ''veritas
Veritas is the name given to the Roman virtue of truthfulness, which was considered one of the main virtues any good Roman should possess. The Greek goddess of truth is Aletheia (Ancient Greek: ). The German philosopher Martin Heidegger argues ...
''.
Whitehead (1861–1947)
Alfred North Whitehead, a British mathematician who became an American philosopher, said: "There are no whole truths; all truths are half-truths. It is trying to treat them as whole truths that plays the devil".
The logical progression or connection of this line of thought is to conclude that truth can lie, since half-truth
A half-truth is a deceptive statement that includes some element of truth. The statement might be partly true, the statement may be totally true, but only part of the whole truth, or it may use some deceptive element, such as improper punctuation, ...
s are deceptive and may lead to a false conclusion.
Peirce (1839–1914)
Pragmatists
Pragmatism is a philosophical tradition that considers words and thought as tools and instruments for prediction, problem solving, and action, and rejects the idea that the function of thought is to describe, represent, or mirror reality. ...
like C. S. Peirce take truth to have some manner of essential relation to human practices for inquiring into and discovering truth, with Peirce himself holding that truth is what human inquiry would find out on a matter, if our practice of inquiry were taken as far as it could profitably go: "The opinion which is fated to be ultimately agreed to by all who investigate, is what we mean by the truth..."
Nishida (1870–1945)
According to Kitaro Nishida, "knowledge of things in the world begins with the differentiation of unitary consciousness into knower and known and ends with self and things becoming one again. Such unification takes form not only in knowing but in the valuing (of truth) that directs knowing, the willing that directs action, and the feeling or emotive reach that directs sensing."
Fromm (1900–1980)
Erich Fromm finds that trying to discuss truth as "absolute truth" is sterile and that emphasis ought to be placed on "optimal truth". He considers truth as stemming from the survival imperative of grasping one's environment physically and intellectually, whereby young children instinctively seek truth so as to orient themselves in "a strange and powerful world". The accuracy of their perceived approximation of the truth will therefore have direct consequences on their ability to deal with their environment. Fromm can be understood to define truth as a functional approximation of reality. His vision of optimal truth is described partly in ''Man for Himself: An Inquiry into the Psychology of Ethics'' (1947), from which excerpts are included below.
: the dichotomy between 'absolute = perfect' and 'relative = imperfect' has been superseded in all fields of scientific thought, where "it is generally recognized that there is no absolute truth but nevertheless that there are objectively valid laws and principles".
: In that respect, "a scientifically or rationally valid statement means that the power of reason is applied to all the available data of observation without any of them being suppressed or falsified for the sake of the desired result". The history of science is "a history of inadequate and incomplete statements, and every new insight makes possible the recognition of the inadequacies of previous propositions and offers a springboard for creating a more adequate formulation."
: As a result "the history of thought is the history of an ever-increasing approximation to the truth. Scientific knowledge is not absolute but optimal; it contains the optimum of truth attainable in a given historical period." Fromm furthermore notes that "different cultures have emphasized various aspects of the truth" and that increasing interaction between cultures allows for these aspects to reconcile and integrate, increasing further the approximation to the truth.
Foucault (1926–1984)
Truth, says Michel Foucault, is problematic when any attempt is made to see truth as an "objective" quality. He prefers not to use the term truth itself but "Regimes of Truth". In his historical investigations he found truth to be something that was itself a part of, or embedded within, a given power structure. Thus Foucault's view shares much in common with the concepts of Nietzsche
Friedrich Wilhelm Nietzsche (; or ; 15 October 1844 – 25 August 1900) was a German philosopher, prose poet, cultural critic, philologist, and composer whose work has exerted a profound influence on contemporary philosophy. He began his car ...
. Truth for Foucault is also something that shifts through various episteme
In philosophy, episteme (; french: épistémè) is a term that refers to a principle system of understanding (i.e., knowledge), such as scientific knowledge or practical knowledge. The term comes from the Ancient Greek verb grc, ἐπῐ́ ...
throughout history.
Baudrillard (1929–2007)
Jean Baudrillard
Jean Baudrillard ( , , ; 27 July 1929 – 6 March 2007) was a French sociologist, philosopher and poet with interest in cultural studies. He is best known for his analyses of media, contemporary culture, and technological communication, as ...
considered truth to be largely simulated, that is pretending to have something, as opposed to dissimulation, pretending to not have something. He took his cue from iconoclasts whom he claims knew that images of God demonstrated that God did not exist.[Jean Baudrillard. Simulacra and Simulation. Michigan: Michigan University Press, 1994.] Baudrillard wrote in "Precession of the Simulacra":
::The simulacrum
A simulacrum (plural: simulacra or simulacrums, from Latin '' simulacrum'', which means "likeness, semblance") is a representation or imitation of a person or thing. The word was first recorded in the English language in the late 16th century, u ...
is never that which conceals the truth—it is the truth which conceals that there is none. The simulacrum is true.
::—Ecclesiastes
Some examples of simulacra
A simulacrum (plural: simulacra or simulacrums, from Latin '' simulacrum'', which means "likeness, semblance") is a representation or imitation of a person or thing. The word was first recorded in the English language in the late 16th century, u ...
that Baudrillard cited were: that prisons simulate the "truth" that society is free; scandals (e.g., Watergate) simulate that corruption is corrected; Disney simulates that the U.S. itself is an adult place. Though such examples seem extreme, such extremity is an important part of Baudrillard's theory. For a less extreme example, movies usually end with the bad being punished, humiliated, or otherwise failing, thus affirming for viewers the concept that the good end happily and the bad unhappily, a narrative which implies that the status quo and established power structures are largely legitimate.
Other contemporary positions
Truthmaker theory
Truthmaker theory is "the branch of metaphysics that explores the relationships between what is true and what exists". The basic intuition behind truthmaker theory is that truth depends on being. For example, a perceptual experience of a green tr ...
is "the branch of metaphysics
Metaphysics is the branch of philosophy that studies the fundamental nature of reality, the first principles of being, identity and change, space and time, causality, necessity, and possibility. It includes questions about the nature of conscio ...
that explores the relationships between what is true and what exists". It is different from substantive theories of truth in the sense that it doesn't aim at giving a definition of what truth is. Instead, it has the goal of ''determining'' how truth depends on being.
Theological views
Hinduism
In Hinduism
Hinduism () is an Indian religion or '' dharma'', a religious and universal order or way of life by which followers abide. As a religion, it is the world's third-largest, with over 1.2–1.35 billion followers, or 15–16% of the global p ...
, truth is defined as "unchangeable", "that which has no distortion", "that which is beyond distinctions of time, space, and person", "that which pervades the universe in all its constancy". The human body, therefore, is not completely true as it changes with time, for example. There are many references, properties and explanations of truth by Hindu sages that explain varied facets of truth, such as the national motto of India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
: " Satyameva Jayate" (Truth alone wins), as well as "Satyam muktaye" (Truth liberates), "Satya' is 'Parahit'artham' va'unmanaso yatha'rthatvam' satyam" (Satya is the benevolent use of words and the mind for the welfare of others or in other words responsibilities is truth too), "When one is firmly established in speaking truth, the fruits of action become subservient to him (patanjali yogasutras, sutra number 2.36), "The face of truth is covered by a golden bowl. ''Unveil it, O Pusan (Sun), so that I who have truth as my duty (satyadharma) may see it!''" (Brhadaranyaka V 15 1–4 and the brief IIsa Upanisad 15–18), Truth is superior to silence (Manusmriti
The ''Manusmṛiti'' ( sa, मनुस्मृति), also known as the ''Mānava-Dharmaśāstra'' or Laws of Manu, is one of the many legal texts and constitution among the many ' of Hinduism. In ancient India, the sages often wrote thei ...
), etc. Combined with other words, satya acts as a modifier, like ''ultra'' or ''highest'', or more literally ''truest'', connoting ''purity and excellence''. For example, satyaloka is the "highest heaven" and Satya Yuga is the "golden age" or best of the four cyclical cosmic ages in Hinduism, and so on.
Buddhism
In Buddhism
Buddhism ( , ), also known as Buddha Dharma and Dharmavinaya (), is an Indian religions, Indian religion or Indian philosophy#Buddhist philosophy, philosophical tradition based on Pre-sectarian Buddhism, teachings attributed to the Buddha. ...
, particularly in the Mahayana
''Mahāyāna'' (; "Great Vehicle") is a term for a broad group of Buddhist traditions, texts, philosophies, and practices. Mahāyāna Buddhism developed in India (c. 1st century BCE onwards) and is considered one of the three main existing br ...
tradition, the notion of truth is often divided into the two truths doctrine
The Buddhist doctrine of the two truths (Sanskrit: ''dvasatya,'' ) differentiates between two levels of ''satya'' (Sanskrit; Pali: ''sacca''; word meaning "truth" or "reality") in the teaching of the Śākyamuni Buddha: the "conventional" or "p ...
, which consists of relative or conventional truth and ultimate truth. The former refers to truth that is based on common understanding among ordinary people and is accepted as a practical basis for communication of higher truths. Ultimate truth necessarily transcends logic in the sphere of ordinary experience, and recognizes such phenomena as illusory. Mādhyamaka
Mādhyamaka ("middle way" or "centrism"; ; Tibetan: དབུ་མ་པ ; ''dbu ma pa''), otherwise known as Śūnyavāda ("the emptiness doctrine") and Niḥsvabhāvavāda ("the no ''svabhāva'' doctrine"), refers to a tradition of Buddhist ...
philosophy asserts that any doctrine can be analyzed with both divisions of truth. Affirmation and negation belong to relative and absolute truth respectively. Political law is regarded as relative, while religious law is absolute.
Christianity
Christianity
Christianity is an Abrahamic monotheistic religion based on the life and teachings of Jesus of Nazareth. It is the world's largest and most widespread religion with roughly 2.38 billion followers representing one-third of the global pop ...
has a soteriological
Soteriology (; el, wikt:σωτηρία, σωτηρία ' "salvation" from wikt:σωτήρ, σωτήρ ' "savior, preserver" and wikt:λόγος, λόγος ' "study" or "word") is the study of Doctrine, religious doctrines of salvation. Salvation ...
view of truth. According to the Bible
The Bible (from Koine Greek , , 'the books') is a collection of religious texts or scriptures that are held to be sacred in Christianity, Judaism, Samaritanism, and many other religions. The Bible is an anthologya compilation of texts ...
in John 14:6, Jesus
Jesus, likely from he, יֵשׁוּעַ, translit=Yēšūaʿ, label= Hebrew/ Aramaic ( AD 30 or 33), also referred to as Jesus Christ or Jesus of Nazareth (among other names and titles), was a first-century Jewish preacher and religiou ...
is quoted as having said "I am the way, the truth and the life: no man cometh unto the Father, but by me".
See also
* Asha
* Confirmation holism
* Contextualism
* Degree of truth
* Disposition
* Eclecticism
* Epistemic theories of truth
* Imagination
* Independence (probability theory)
* Invariant (mathematics)
* McNamara fallacy
* Normative science
* ''On Truth and Lies in a Nonmoral Sense''
* Perspectivism
* Physical symbol system
* Public opinion
* Relativism
* Religious views on truth
* Revision theory
* Slingshot argument
* Subjectivity
* Tautology (logic)
* Tautology (rhetoric)
* Theory of justification
* Truth prevails
* Truthiness
* Unity of the proposition
* Verisimilitude
Other theorists
* Augustine of Hippo
* Brand Blanshard
* Hartry Field
* Gottlob Frege
* Paul Horwich
* Harold Joachim
* Karl Popper
Notes
References
* Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of ph ...
, "The Categories", Harold P. Cooke (trans.), pp. 1–109 in ''Aristotle, Volume 1'', Loeb Classical Library, Heinemann (book publisher), William Heinemann, London, 1938.
* Aristotle, "On Interpretation", Harold P. Cooke (trans.), pp. 111–79 in ''Aristotle, Volume 1'', Loeb Classical Library, William Heinemann, London, 1938.
* Aristotle, "Prior Analytics", Hugh Tredennick (trans.), pp. 181–531 in ''Aristotle, Volume 1'', Loeb Classical Library, William Heinemann, London, 1938.
* Aristotle, "On the Soul" (''De Anima''), W. S. Hett (trans.), pp. 1–203 in ''Aristotle, Volume 8'', Loeb Classical Library, William Heinemann, London, 1936.
* Robert Audi, Audi, Robert (ed., 1999), ''The Cambridge Dictionary of Philosophy'', Cambridge University Press, Cambridge, 1995. 2nd edition, 1999. Cited as CDP.
* James Mark Baldwin, Baldwin, James Mark (ed., 1901–1905), ''Dictionary of Philosophy and Psychology'', 3 volumes in 4, Macmillan, New York.
* Charles A. Baylis, Baylis, Charles A. (1962), "Truth", pp. 321–22 in Dagobert D. Runes (ed.), ''Dictionary of Philosophy'', Littlefield, Adams, and Company, Totowa, NJ.
* A. Cornelius Benjamin, Benjamin, A. Cornelius (1962), "Coherence Theory of Truth", p. 58 in Dagobert D. Runes (ed.), ''Dictionary of Philosophy'', Littlefield, Adams, and Company, Totowa, NJ.
* Blackburn, Simon, and Simmons, Keith (eds., 1999), ''Truth'', Oxford University Press, Oxford. Includes papers by James, Ramsey, Russell, Tarski, and more recent work.
* Subrahmanyan Chandrasekhar, Chandrasekhar, Subrahmanyan (1987), ''Truth and Beauty. Aesthetics and Motivations in Science'', University of Chicago Press, Chicago, IL.
* C.C. Chang, Chang, C.C., and H.J. Keisler, Keisler, H.J., ''Model Theory'', North-Holland, Amsterdam, Netherlands, 1973.
* Noam Chomsky, Chomsky, Noam (1995), ''The Minimalist Program'', MIT Press, Cambridge, Massachusetts.
* Alonzo Church, Church, Alonzo (1962a), "Name Relation, or Meaning Relation", p. 204 in Dagobert D. Runes (ed.), ''Dictionary of Philosophy'', Littlefield, Adams, and Company, Totowa, NJ.
* Church, Alonzo (1962b), "Truth, Semantical", p. 322 in Dagobert D. Runes (ed.), ''Dictionary of Philosophy'', Littlefield, Adams, and Company, Totowa, NJ.
* Clifford, W.K. (1877), "The Ethics of Belief and Other Essays". (Prometheus Books, 1999)
infidels.org
* John Dewey, Dewey, John (1900–1901), ''Lectures on Ethics 1900–1901'', Donald F. Koch (ed.), Southern Illinois University Press, Carbondale and Edwardsville, IL.
* Dewey, John (1932), ''Theory of the Moral Life'', Part 2 of John Dewey and James H. Tufts, ''Ethics'', Henry Holt and Company, New York, 1908. 2nd edition, Holt, Rinehart, and Winston, 1932. Reprinted, Arnold Isenberg (ed.), Victor Kestenbaum (pref.), Irvingtion Publishers, New York, 1980.
* Dewey, John (1938), ''Logic: The Theory of Inquiry'' (1938), Holt and Company, New York. Reprinted, ''John Dewey, The Later Works, 1925–1953, Volume 12: 1938'', Jo Ann Boydston (ed.), Southern Illinois University Press, Carbondale and Edwardsville, IL, 1986.
* Field, Hartry (2001), ''Truth and the Absence of Fact'', Oxford University Press, Oxford.
* Michel Foucault, Foucault, Michel (1997), ''Essential Works of Foucault, 1954–1984, Volume 1, Ethics: Subjectivity and Truth'', Paul Rabinow (ed.), Robert Hurley et al. (trans.), The New Press, New York.
* Garfield, Jay L., and Kiteley, Murray (1991), ''Meaning and Truth: The Essential Readings in Modern Semantics'', Paragon House, New York.
* Gupta, Anil (2001), "Truth", in Lou Goble (ed.), ''The Blackwell Guide to Philosophical Logic'', Blackwell Publishers, Oxford.
* Gupta, Anil and Nuel Belnap, Belnap, Nuel. (1993). ''The Revision Theory of Truth''. MIT Press.
* Susan Haack, Haack, Susan (1993), ''Evidence and Inquiry: Towards Reconstruction in Epistemology'', Blackwell Publishers, Oxford.
* Jürgen Habermas, Habermas, Jürgen (1976), "What Is Universal Pragmatics?", 1st published, "Was heißt Universalpragmatik?", ''Sprachpragmatik und Philosophie'', Karl-Otto Apel (ed.), Suhrkamp Verlag, Frankfurt am Main. Reprinted, pp. 1–68 in Jürgen Habermas, ''Communication and the Evolution of Society'', Thomas McCarthy (trans.), Beacon Press, Boston, 1979.
* Habermas, Jürgen (1990), ''Moral Consciousness and Communicative Action'', Christian Lenhardt and Shierry Weber Nicholsen (trans.), Thomas McCarthy (intro.), MIT Press, Cambridge, Massachusetts.
* Habermas, Jürgen (2003), ''Truth and Justification'', Barbara Fultner (trans.), MIT Press, Cambridge, Massachusetts.
* Georg Hegel, Hegel, Georg, (1977), ''Phenomenology of Spirit'', Oxford University Press, Oxford, .
* Horwich, Paul, (1988), ''Truth'', 2nd edition, Oxford University Press, Oxford.
* William James, James, William (1904), ''A World of Pure Experience''.
* James, William (1907), ''Pragmatism, A New Name for Some Old Ways of Thinking, Popular Lectures on Philosophy'', Longmans, Green, and Company, New York.
* James, William (1909), ''The Meaning of Truth, A Sequel to 'Pragmatism'', Longmans, Green, and Company, New York.
* James, William (1912), ''Essays in Radical Empiricism''. Cf. Chapt. 3, "The Thing and its Relations", pp. 92–122.
* James, William (2014), ''William James on Habit, Will, Truth, and the Meaning of Life''. James Sloan Allen (ed.), Frederic C. Beil, Publisher, Savannah, GA.
* Immanuel Kant, Kant, Immanuel (1800), ''Introduction to Logic''. Reprinted, Thomas Kingsmill Abbott (trans.), Dennis Sweet (intro.), Barnes and Noble, New York, 2005.
* Richard Kirkham, Kirkham, Richard L. (1992), ''Theories of Truth: A Critical Introduction'', MIT Press, Cambridge, Massachusetts.
* William Kneale, Kneale, W., and Martha Kneale, Kneale, M. (1962), ''The Development of Logic'', Oxford University Press, London, 1962. Reprinted with corrections, 1975.
* Hans Kreitler, Kreitler, Hans, and Shulamith Kreitler, Kreitler, Shulamith (1972), ''Psychology of the Arts'', Duke University Press, Durham, NC.
* Le Morvan, Pierre (2004), "Ramsey on Truth and Truth on Ramsey", ''British Journal for the History of Philosophy'', 12 (4) 2004, 705–18
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* Charles Sanders Peirce bibliography, Peirce, C.S., Bibliography.
* Charles Sanders Peirce, Peirce, C.S., ''Collected Papers of Charles Sanders Peirce'', vols. 1–6, Charles Hartshorne and Paul Weiss (philosopher), Paul Weiss (eds.), vols. 7–8, Arthur W. Burks (ed.), Harvard University Press, Cambridge, Massachusetts, 1931–1935, 1958. Cited as CP vol.para.
* Peirce, C.S. (1877), "The Fixation of Belief", ''Popular Science Monthly'' 12 (1877), 1–15. Reprinted (CP 5.358–387), (CE 3, 242–257), (EP 1, 109–123)
Eprint
* Peirce, C.S. (1901), "Truth and Falsity and Error" (in part), pp. 718–20 in J.M. Baldwin (ed.), ''Dictionary of Philosophy and Psychology'', vol. 2. Reprinted, CP 5.565–573.
* Michael Polanyi, Polanyi, Michael (1966), ''The Tacit Dimension'', Doubleday and Company, Garden City, NY.
* W.V. Quine, Quine, W.V. (1956), "Quantifiers and Propositional Attitudes", ''Journal of Philosophy'' 53 (1956). Reprinted, pp. 185–96 in Quine (1976), ''Ways of Paradox''.
* Quine, W.V. (1976), ''The Ways of Paradox, and Other Essays'', 1st edition, 1966. Revised and enlarged edition, Harvard University Press, Cambridge, Massachusetts, 1976.
* Quine, W.V. (1980 a), ''From a Logical Point of View, Logico-Philosophical Essays'', 2nd edition, Harvard University Press, Cambridge, Massachusetts.
* Quine, W.V. (1980 b), "Reference and Modality", pp. 139–59 in Quine (1980 a), ''From a Logical Point of View''.
* John Rajchman, Rajchman, John, and Cornel West, West, Cornel (ed., 1985), ''Post-Analytic Philosophy'', Columbia University Press, New York.
* Frank Plumpton Ramsey, Ramsey, F.P. (1927), "Facts and Propositions", ''Aristotelian Society Supplementary Volume 7'', 153–70. Reprinted, pp. 34–51 in F.P. Ramsey, ''Philosophical Papers'', David Hugh Mellor (ed.), Cambridge University Press, Cambridge, 1990.
* Ramsey, F.P. (1990), ''Philosophical Papers'', David Hugh Mellor (ed.), Cambridge University Press, Cambridge.
* John Rawls, Rawls, John (2000), ''Lectures on the History of Moral Philosophy'', Barbara Herman (ed.), Harvard University Press, Cambridge, Massachusetts.
* Richard Rorty, Rorty, R. (1979), ''Philosophy and the Mirror of Nature'', Princeton University Press, Princeton, NJ.
* Bertrand Russell, Russell, Bertrand (1912), ''The Problems of Philosophy'', 1st published 1912. Reprinted, Galaxy Book, Oxford University Press, New York, 1959. Reprinted, Prometheus Books, Buffalo, NY, 1988.
* Russell, Bertrand (1918), "The Philosophy of Logical Atomism", ''The Monist'', 1918. Reprinted, pp. 177–281 in ''Logic and Knowledge: Essays 1901–1950'', Robert Charles Marsh (ed.), Unwin Hyman, London, 1956. Reprinted, pp. 35–155 in ''The Philosophy of Logical Atomism'', David Pears (ed.), Open Court, La Salle, IL, 1985.
* Russell, Bertrand (1956), ''Logic and Knowledge: Essays 1901–1950'', Robert Charles Marsh (ed.), Unwin Hyman, London, 1956. Reprinted, Routledge, London, 1992.
* Russell, Bertrand (1985), ''The Philosophy of Logical Atomism'', David Pears (ed.), Open Court, La Salle, IL.
* Arthur Schopenhauer, Schopenhauer, Arthur, (1974), ''On the Fourfold Root of the Principle of Sufficient Reason'', Open Court, La Salle, IL, .
* Ninian Smart, Smart, Ninian (1969), ''The Religious Experience of Mankind'', Charles Scribner's Sons, New York.
* Alfred Tarski, Tarski, A., ''Logic, Semantics, Metamathematics: Papers from 1923 to 1938'', J.H. Woodger (trans.), Oxford University Press, Oxford, 1956. 2nd edition, John Corcoran (ed.), Hackett Publishing, Indianapolis, IN, 1983.
* Anthony F.C. Wallace, Wallace, Anthony F.C. (1966), ''Religion: An Anthropological View'', Random House, New York.
Reference works
* Robert Audi, Audi, Robert (ed., 1999), ''The Cambridge Dictionary of Philosophy'', Cambridge University Press, Cambridge, 1995. 2nd edition, 1999. Cited as CDP.
* Simon Blackburn, Blackburn, Simon (1996), ''The Oxford Dictionary of Philosophy'', Oxford University Press, Oxford, 1994. Paperback edition with new Chronology, 1996. Cited as ODP.
* Dagobert D. Runes, Runes, Dagobert D. (ed.), ''Dictionary of Philosophy'', Littlefield, Adams, and Company, Totowa, NJ, 1962.
* ''Webster's New International Dictionary of the English Language, Second Edition, Unabridged'' (1950), W.A. Neilson, T.A. Knott, P.W. Carhart (eds.), G. & C. Merriam Company, Springfield, MA. Cited as MWU.
* ''Webster's Ninth New Collegiate Dictionary'' (1983), Frederick C. Mish (ed.), Merriam–Webster Inc., Springfield, MA. Cited as MWC.
External links
An Introduction to Truth
by Paul Newall, aimed at beginners.
* Internet Encyclopedia of Philosophy:
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"Truth"
*
"Pluralist Theories of Truth"
*
Theory"
*
Theory of Truth"
* Stanford Encyclopedia of Philosophy:
*
Truth
*
Coherence theory of truth
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Correspondence theory of truth
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Deflationary theory of truth
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Identity theory of truth
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Revision theory of truth
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Tarski's definition of truth
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Axiomatic theories of truth
{{Authority control
Truth,
Concepts in epistemology
Concepts in logic
Concepts in metaphysics
Ethical principles
Meaning (philosophy of language)
Ontology
Philosophical logic
Philosophy of mind
Reality
Theories of truth
Virtue