Cartesian doubt is a form of methodological skepticism associated with the writings and methodology of

René Descartes René Descartes ( or ; ; Latinized: Renatus Cartesius; 31 March 1596 – 11 February 1650) was a French philosopher, scientist, and mathematician, widely considered a seminal figure in the emergence of modern philosophy and science. Ma ...

(March 31, 1596Feb 11, 1650). Scruton, R.
''Modern Philosophy: An Introduction and Survey''
(London: Penguin Books, 1994). Leiber, J., ed., ''A Philosophical Glossary'', Philosophy Department,

University of Houston The University of Houston (UH) is a public research university in Houston, Texas. Founded in 1927, UH is a member of the University of Houston System and the university in Texas with over 47,000 students. Its campus, which is primarily in s ...

, 2001
p. 88
Cartesian doubt is also known as Cartesian skepticism, methodic doubt, methodological skepticism, universal doubt, systematic doubt, or hyperbolic doubt. Cartesian doubt is a systematic process of being skeptical about (or doubting) the truth of one's beliefs, which has become a characteristic method in philosophy. Additionally, Descartes' method has been seen by many as the root of the modern scientific method. This method of doubt was largely popularized in Western philosophy by René Descartes, who sought to doubt the truth of all beliefs in order to determine which he could be certain were true. It is the basis for Descartes' statement, "''

Cogito ergo sum The Latin , usually translated into English as "I think, therefore I am", is the "first principle" of René Descartes's philosophy. He originally published it in French as , in his 1637 ''Discourse on the Method'', so as to reach a wider audien ...

''" (I think, therefore I am). A fuller version of his phrase: "''dubito ergo cogito, cogito ergo sum''" translates to "I doubt therefore I think, I think therefore I exist." ''Sum'' translated as "I exist" (per various Latin to English dictionaries) presents a much larger and clearer meaning to the phrase. Methodological skepticism is distinguished from

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 ...

in that methodological skepticism is an approach that subjects all knowledge claims to scrutiny with the goal of sorting out true from false claims, whereas philosophical skepticism is an approach that questions the possibility of certain knowledge.

Characteristics

Cartesian doubt is methodological. It uses doubt as a route to certain knowledge by identifying what can't be doubted. The fallibility of sense data in particular is a subject of Cartesian doubt. There are several interpretations as to the objective of Descartes' skepticism. Prominent among these is a

foundationalist Foundationalism concerns philosophical theories of knowledge resting upon non-inferential justified belief, or some secure foundation of certainty such as a conclusion inferred from a basis of sound premises.Simon Blackburn, ''The Oxford Dictio ...

account, which claims that Descartes' skepticism aims to eliminate all belief that it is possible to doubt, thus leaving only

basic belief Basic beliefs (also commonly called foundational beliefs or core beliefs) are, under the epistemological view called foundationalism, the axioms of a belief system. Categories of beliefs Foundationalism holds that all beliefs must be justifi ...

s (also known as foundational beliefs). From these indubitable basic beliefs, Descartes then attempts to derive further knowledge. It's an archetypal and significant example that epitomizes the Continental Rational schools of philosophy.

Mario Bunge Mario Augusto Bunge (; ; September 21, 1919 – February 24, 2020) was an Argentine-Canadian philosopher and physicist. His philosophical writings combined scientific realism, systemism, materialism, emergentism, and other principles. He was ...

argues that methodological skepticism presupposes that scientific theories and methods satisfy certain philosophical requirements:

Idealism In philosophy, the term idealism identifies and describes metaphysical perspectives which assert that reality is indistinguishable and inseparable from perception and understanding; that reality is a mental construct closely connected t ...

, materialism,

realism Realism, Realistic, or Realists may refer to: In the arts *Realism (arts), the general attempt to depict subjects truthfully in different forms of the arts Arts movements related to realism include: *Classical Realism *Literary realism, a move ...

rationalism In philosophy, rationalism is the epistemological view that "regards reason as the chief source and test of knowledge" or "any view appealing to reason as a source of knowledge or justification".Lacey, A.R. (1996), ''A Dictionary of Philosophy ...

, empiricism, and systemism, that the data and hypotheses of science constitute a system.

Technique

Descartes' method of hyperbolic doubt included: * Accepting only information you know is true * Breaking down these truths into smaller units * Solving the simple problems first * Making complete lists of further problems Hyperbolic doubt means having the tendency to doubt, since it is an extreme or exaggerated form of doubt. Knowledge in the Cartesian sense means to know something beyond not merely all reasonable doubt, but all possible doubt. In his ''

Meditations on First Philosophy ''Meditations on First Philosophy, in which the existence of God and the immortality of the soul are demonstrated'' ( la, Meditationes de Prima Philosophia, in qua Dei existentia et animæ immortalitas demonstratur) is a philosophical treatise ...

'' (1641), Descartes resolved to systematically doubt that any of his beliefs were true, in order to build, from the ground up, a belief system consisting of only certainly true beliefs; his end goal—or at least a major one—was to find an undoubtable basis for the sciences. Consider Descartes' opening lines of the ''Meditations'':

Descartes' method

René Descartes, the originator of Cartesian doubt, put all beliefs, ideas, thoughts, and matter in doubt. He showed that his grounds, or reasoning, for any knowledge could just as well be false. Sensory experience, the primary mode of knowledge, is often erroneous and therefore must be doubted. For instance, what one is seeing may very well be a

hallucination A hallucination is a perception in the absence of an external stimulus that has the qualities of a real perception. Hallucinations are vivid, substantial, and are perceived to be located in external objective space. Hallucination is a combinati ...

. There is nothing that proves it cannot be. In short, if there is any way a belief can be disproved, then its grounds are insufficient. From this, Descartes proposed two arguments, the dream and the demon.

The dream argument

Descartes, knowing that the context of our dreams, while possibly unbelievable, are often lifelike, hypothesized that humans can only believe that they are awake. There are no sufficient grounds to distinguish a dream experience from a waking experience. For instance, Subject A sits at the computer, typing this article. Just as much evidence exists to indicate that the act of composing this article is reality as there is evidence to demonstrate the opposite. Descartes conceded that we live in a world that can create such ideas as dreams. However, by the end of ''The Meditations'', he concludes that we can distinguish dream from reality at least in retrospect:

"But when I distinctly see where things come from and where and when they come to me, and when I can connect my perceptions of them with the whole of the rest of my life without a break, then I am quite certain that when I encounter these things I am not asleep but awake."—''Descartes: Selected Philosophical Writings''

The Evil Demon

Descartes reasoned that our very own experience may very well be controlled by an ''evil demon'' of sorts. This demon is as clever and deceitful as he is powerful. He could have created a superficial world that we may think we live in. As a result of this doubt, sometimes termed the Malicious Demon Hypothesis, Descartes found that he was unable to trust even the simplest of his perceptions. In '' Meditation I'', Descartes stated that if one were mad, even briefly, the insanity might have driven man into believing that what we thought was true could be merely our minds deceiving us. He also stated that there could be ' some malicious, powerful, cunning demon' that had deceived us, preventing us from judging correctly. Descartes argued that all his senses were lying, and since your senses can easily fool you, his idea of an infinitely powerful being must be true—since that idea could have only been put there by an infinitely powerful being who would have no reason for deceit.

I think, therefore I am

While methodic doubt has a nature, one need not hold that knowledge is impossible to apply the method of doubt. Indeed, Descartes' attempt to apply the method of doubt to the existence of himself spawned the proof of his famous saying, "''

Cogito, ergo sum The Latin , usually translated into English as "I think, therefore I am", is the "first principle" of René Descartes's philosophy. He originally published it in French as , in his 1637 ''Discourse on the Method'', so as to reach a wider audie ...

''" (I think, therefore I am). That is, Descartes tried to doubt his own existence, but found that even his doubting showed that he existed, since he could not doubt if he did not exist.Scruton, ibid.
p. 56

References

External links

* * * * Descartes, René. (1641)
''Meditations on First Philosophy''
In Cottingham, et al. (eds.), 1984. *
Dictionary of Philosophy of Mind
{{Portal bar, Philosophy, Psychology Skepticism René Descartes Philosophy of science Philosophical methodology Theory of mind Epistemological theories Epistemology of science Doubt