Common sense is defined by Merriam-Webster as, "sound and prudent judgment based on a simple perception of the situation or facts." Thus, "common sense" (in this view) equates to the knowledge and experience which most people already have, or which the person using the term believes that they do or should have. The Cambridge Dictionary defines it as, "the basic level of practical knowledge and judgment that we all need to help us live in a reasonable and safe way".
Whichever definition is used, identifying particular items of knowledge as "common sense" is difficult. Philosophers may choose to avoid using the phrase when using precise language. But common sense remains a perennial topic in epistemology and many philosophers make wide use of the concept or at least refer to it. Some related concepts include intuitions, pre-theoretic belief, ordinary language, the frame problem, foundational beliefs, good sense, endoxa, axioms, wisdom, folk wisdom, folklore, and public opinion.
Common-sense ideas tend to relate to events within human experience (such as good will), and thus appear commensurate with human scale. Humans lack any common-sense intuition of, for example, the behavior of the universe at subatomic distances [see Quantum mechanics], or of speeds approaching that of light [see Special relativity]. Often ideas that may be considered to be true by common sense are in fact false.
According to Aristotle, the common sense (Sensus communis) is an actual power of inner sensation (as opposed to the external five senses (Five wits)) whereby the various objects of the external senses (color for sight, sound for hearing, etc.) are united and judged, such that what one senses by "common sense" is the substance (or existing thing) in which the various attributes inhere (so, for example, a sheep is able to sense a wolf, not just the color of its fur, the sound of its howl, its odor, and other sensible attributes.) It was not, unlike later developments, considered to be on the level of rationality, which properly did not exist in the lower animals, but only in man; this irrational character was because animals not possessing rationality nevertheless required the use of the common sense in order to sense, for example, the difference between this or that thing, and not merely the pleasure and pain of various disparate sensations. This also contributes to the understanding held by the Scholastics that when one senses, one senses something, and not just a diversity of sensible phenomena.
Common sense, in this view, differs from later views in that it is concerned with the way one receives sensation, and not with belief, or wisdom held by many; accordingly, it is "common", not in the sense of being shared among individuals, or being a genus of the different external senses, but inasmuch as it is a principle which governs the activity of the external senses.
In Cicero, common sense was the common practice, custom, speech, views, and mentality of the crowd whose tastes the orator had to take into account if he were to influence them (De Oratore, I, 3, 12). At the same time it was the tacit sense and collection of spontaneous judgments which all men possess by nature and which permits them to discern good from evil (De Oratore, III, 50, 195).
Locke and the empiricists
John Locke proposed one meaning of "common sense" in his An Essay Concerning Human Understanding. This interpretation builds on phenomenological experience. Each of the senses gives input, and then something integrates the sense-data into a single impression. This something Locke sees as the common sense — the sense of things in common between disparate impressions. It therefore allies with "fancy", and opposes "judgement", or the capacity to divide like things into separates. The French theologian Jacques-Bénigne Bossuet arguably developed this theory a decade before Locke. Each of the empiricist philosophers approaches the problem of the unification of sense-data in their own way, giving various names to the operation. However, the approaches agree that a sense in the human understanding exists that sees commonality and does the combining: "common sense" has the same meaning.
Appeal to common sense characterises a general epistemological orientation called epistemological particularism (the appellation derives from Roderick Chisholm (1916–1999)). This orientation contrasts with epistemological Methodism. The particularist gathers a list of propositions that seem obvious and unassailable and then requires consistency with this set of propositions as a condition of adequacy for any abstract philosophical theory. (Particularism allows, however, rejection of an entry on the list for inconsistency with other, seemingly more secure, entries.) Epistemological Methodists, on the other hand, begin with a theory of cognition or justification and then apply it to see which of our pre-theoretical beliefs survive. Reid and Moore represent paradigmatic particularists, while Descartes and Hume stand as paradigmatic Methodists. Methodist methodology tends toward skepticism, as the rules for acceptable or rational belief tend to be very restrictive (for instance, Descartes demanded the elimination of doubt; and Hume required the construction of acceptable belief entirely from impressions and ideas).
Particularists, on the other hand, tend toward a kind of conservatism, granting perhaps an undue privilege to beliefs in which we happen to have confidence. One interesting question asks whether epistemological thought can mix the methodologies. In such a case, does it not become problematical to attempt logic, metaphysics and epistemology with the absence of original assumptions stemming from common sense? Particularism, applied to ethics and politics, may seem to simply entrench prejudice and other contingent products of social inculcation (compare cultural determinism). Can one provide a principled distinction between areas of inquiry where reliance on the dictates of common sense seems legitimate (because necessary) and areas where it seems illegitimate (as for example an obstruction to intellectual and practical progress)? A meta-philosophical discussion of common sense may then, indeed, proceed: What is common sense? Supposing that one cannot give a precise characterization of it: does that mean that appeal to common sense remains off-limits in philosophy? What utility does it have to discern whether a belief is a matter of common sense or not? And under what circumstances, if any, might one advocate a view that seems to run contrary to common sense? Should considerations of common sense play any decisive role in philosophy? Common sense in politics is the same as: ordinary, status quo, non-innovative, safe (popular) ideas. If not common sense, then could another similar concept (perhaps "intuition") play such a role? In general, does epistemology have "philosophical starting points", and if so, how can one characterize them? Supposing that no beliefs exist which we will willingly hold come what may, do there though exist some we ought to hold more stubbornly at least?
In moral philosophy, common sense forms the ubiquitous concept shared by all, and is more formally known as common-sense morality, based on individual moral intuitions. This often sets the stage for specific discussions with established moral theories, such as consequentialism.
- McCarthy's advice-taker proposal of 1958 arguably represents the first scheme to use logic for representing common-sense knowledge in mathematical logic and using an automated theorem prover to derive answers to questions expressed in logical form. Compare Leibniz's calculus ratiocinator and characteristica universalis.
- The Cyc project attempts to provide a basis of common-sense knowledge for artificial-intelligence systems.
- The Open Mind Common Sense project resembles the Cyc project, except that it, like other on-line collaborative projects such as Wikipedia, depends on the contributions of thousands of individuals across the World Wide Web .
|Wikiquote has a collection of quotations related to: Common sense|
|Look up common sense in Wiktionary, the free dictionary.|
- common sense, Merriam-Webster's Online Dictionary.
- common sense, Cambridge Dictionaries Online.
- Aristotle: De Anima, Book III, Part 2
- Thomas Aquinas: Commentary on De Anima, Book II, Chapter 2, Lectio Three
- Thomas Aquinas: Summa Theologiae, Pars I, Q. 78 A. 4 Ad 1
- http://www.rosmini-in-english.org/NewEssay_01/NE1_Sect3/NE1_S03C05.htm Antonio Rosmini, New Essay concerning The Origin of Ideas