A principle may relate to a fundamental truth or proposition that serves as the foundation for a system of beliefs or behavior or a chain of reasoning. They provide a guide for behavior or evaluation. A principle can make values explicit, so they are expressed in the form of rules and standards. Principles unpack the values underlying them more concretely so that the values can be more easily operationalized in policy statements and actions. In

law Law is a set of rules that are created and are enforceable by social or governmental institutions to regulate behavior, with its precise definition a matter of longstanding debate. It has been variously described as a science and as the ar ...

, higher order, overarching principles establish

rules Rule or ruling may refer to: Human activity * The exercise of political or personal control by someone with authority or power * Business rule, a rule pertaining to the structure or behavior internal to a business * School rule, a rule tha ...

to be followed, modified by sentencing guidelines relating to context and proportionality. In science and nature, a principle may define the essential characteristics of the system, or reflect the system's designed purpose. The effective operation would be impossible if any one of the principles was to be ignored. A system may be explicitly based on and implemented from a document of principles as was done in IBM's 360/370 ''Principles of Operation''. It is important to differentiate an operational principle, including reference to 'first principles' from higher order 'guiding' or 'exemplary' principles, such as equality, justice and sustainability. Higher-order, 'superordinate' principles (Super-Ps) provide a basis for resolving differences and building agreement/alignment. Examples of principles are,

entropy Entropy is a scientific concept, most commonly associated with states of disorder, randomness, or uncertainty. The term and the concept are used in diverse fields, from classical thermodynamics, where it was first recognized, to the micros ...

in a number of fields, least action in physics, those in descriptive comprehensive and fundamental law:

doctrine Doctrine (from , meaning 'teaching, instruction') is a codification (law), codification of beliefs or a body of teacher, teachings or instructions, taught principles or positions, as the essence of teachings in a given branch of knowledge or in a ...

s or assumptions forming normative rules of conduct,

separation of church and state The separation of church and state is a philosophical and Jurisprudence, jurisprudential concept for defining political distance in the relationship between religious organizations and the State (polity), state. Conceptually, the term refers to ...

in statecraft, the central dogma of molecular biology, fairness in ethics, etc. In common English, it is a substantive and collective term referring to rule governance, the absence of which, being "unprincipled", is considered a character defect. It may also be used to declare that a reality has diverged from some ideal or norm as when something is said to be true only "in principle" but not in fact.

As law

As moral law

A principle represents values that orient and rule the conduct of persons in a particular society. To "act on principle" is to act in accordance with one's moral ideals. Principles are absorbed in childhood through a process of

socialization In sociology, socialization (also socialisation – see American and British English spelling differences#-ise, -ize (-isation, -ization), spelling differences) is the process of Internalisation (sociology), internalizing the Norm (social), norm ...

. There is a presumption of liberty of individuals that is restrained. Exemplary principles include First, do no harm, the

Golden Rule The Golden Rule is the principle of treating others as one would want to be treated by them. It is sometimes called an ethics of reciprocity, meaning that one should reciprocate to others how one would like them to treat the person (not neces ...

and the ''

Doctrine of the Mean The ''Doctrine of the Mean'' or ''Zhongyong'' is one of the Four Books of classical Chinese philosophy and a central doctrine of Confucianism. The text is attributed to Zisi (Kong Ji), the only grandson of Confucius (Kong Zi). It was origina ...

''.

As a juridic law

It represents a set of values that inspire the written norms that organize the life of a society submitting to the powers of an authority, generally the State. The law establishes a legal obligation, in a coercive way; it therefore acts as principle conditioning of the action that limits the liberty of the individuals. See, for examples, the

territorial principle The territorial principle (also territoriality principle) is a principle of public international law which enables a sovereign state to exercise exclusive jurisdiction over individuals and other legal persons within its territory. It includes both ...

homestead principle The homestead principle is the principle by which one gains ownership of an unowned natural resource by performing an act of original appropriation. Appropriation could be enacted by putting an unowned resource to active use (as with using i ...

, and

precautionary principle The precautionary principle (or precautionary approach) is a broad epistemological, philosophical and legal approach to innovations with potential for causing harm when extensive scientific knowledge on the matter is lacking. It emphasizes cautio ...

As scientific law

Archimedes' principle Archimedes' principle states that the upward buoyant force that is exerted on a body immersed in a fluid, whether fully or partially, is equal to the weight of the fluid that the body displaces. Archimedes' principle is a law of physics fun ...

, relating buoyancy to the weight of displaced water, is an early example of a

in science. Another early one developed by

Malthus Thomas Robert Malthus (; 13/14 February 1766 – 29 December 1834) was an English economist, cleric, and scholar influential in the fields of political economy and demography. In his 1798 book ''An Essay on the Principle of Population'', Mal ...

is the ''population principle'', now called the Malthusian principle. Freud also wrote on principles, especially the

reality principle In Freudian psychology and psychoanalysis, the reality principle () is the ability of the mind to assess the reality of the external world, and to act upon it accordingly, as opposed to acting according to the pleasure principle. The reality prin ...

necessary to keep the id and pleasure principle in check. Biologists use the

principle of priority Priority is a principle in Taxonomy (biology), biological taxonomy by which a valid scientific name is established based on the oldest available name. It is a decisive rule in Botanical nomenclature, botanical and zoological nomenclature to recogn ...

and principle of Binominal nomenclature for precision in naming

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

. There are many principles observed in physics, notably in

cosmology Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe, the cosmos. The term ''cosmology'' was first used in English in 1656 in Thomas Blount's ''Glossographia'', with the meaning of "a speaking of the wo ...

which observes the

mediocrity principle The mediocrity principle is the philosophical notion that "if an item is drawn at random from one of several sets or categories, it's more likely to come from the most numerous category than from any one of the less numerous categories". The prin ...

, the

anthropic principle In cosmology, the anthropic principle, also known as the observation selection effect, is the proposition that the range of possible observations that could be made about the universe is limited by the fact that observations are only possible in ...

, the

principle of relativity In physics, the principle of relativity is the requirement that the equations describing the laws of physics have the same form in all admissible frames of reference. For example, in the framework of special relativity, the Maxwell equations ...

and the

cosmological principle In modern physical cosmology, the cosmological principle is the notion that the spatial distribution of matter in the universe is uniformly isotropic and homogeneous when viewed on a large enough scale, since the forces are expected to act equa ...

. Other well-known principles include the

uncertainty principle The uncertainty principle, also known as Heisenberg's indeterminacy principle, is a fundamental concept in quantum mechanics. It states that there is a limit to the precision with which certain pairs of physical properties, such as position a ...

quantum mechanics Quantum mechanics is the fundamental physical Scientific theory, theory that describes the behavior of matter and of light; its unusual characteristics typically occur at and below the scale of atoms. Reprinted, Addison-Wesley, 1989, It is ...

and the

pigeonhole principle In mathematics, the pigeonhole principle states that if items are put into containers, with , then at least one container must contain more than one item. For example, of three gloves, at least two must be right-handed or at least two must be l ...

and

superposition principle The superposition principle, also known as superposition property, states that, for all linear systems, the net response caused by two or more stimuli is the sum of the responses that would have been caused by each stimulus individually. So th ...

in mathematics.

As axiom or logical fundament

Principle of sufficient reason

The principle states that every event has a rational explanation. The principle has a variety of expressions, all of which are perhaps best summarized by the following: :For every entity ''x'', if ''x'' exists, then there is a sufficient explanation for why ''x'' exists. :For every event ''e'', if ''e'' occurs, then there is a sufficient explanation for why ''e'' occurs. :For every proposition ''p'', if ''p'' is true, then there is a sufficient explanation for why ''p'' is true. However, one realizes that in every sentence there is a direct relation between the predicate and the subject. To say that "the Earth is round", corresponds to a direct relation between the subject and the predicate.

Principle of non-contradiction

According to

Aristotle Aristotle (; 384–322 BC) was an Ancient Greek philosophy, Ancient Greek philosopher and polymath. His writings cover a broad range of subjects spanning the natural sciences, philosophy, linguistics, economics, politics, psychology, a ...

, "It is impossible for the same thing to belong and not to belong at the same time to the same thing and in the same respect." For example, it is not possible that in exactly the same moment and place, it rains and does not rain.

Principle of excluded middle

The principle of the excluding third or "principium tertium exclusum" is a principle of the traditional logic formulated canonically by

Leibniz Gottfried Wilhelm Leibniz (or Leibnitz; – 14 November 1716) was a German polymath active as a mathematician, philosopher, scientist and diplomat who is credited, alongside Sir Isaac Newton, with the creation of calculus in addition to many ...

as: either ''A'' is ''B'' or ''A'' isn't ''B''. It is read the following way: either ''P'' is true, or its denial ¬''P'' is. It is also known as "''tertium non datur''" ('A third (thing) is not'). Classically it is considered to be one of the most important fundamental principles or laws of thought (along with the principles of identity, non-contradiction and sufficient reason).

References

External links

* * ''Actus Essendi'' and the Habit of the First Principle in Thomas Aquinas (New York: Einsiedler Press, 2019)
/span>. {{Authority control Concepts in epistemology Concepts in ethics Concepts in metaphysics Concepts in the philosophy of mind Concepts in the philosophy of science Metaphysics of mind Ontology