AskDefine | Define reason

Dictionary Definition



1 a rational motive for a belief or action; "the reason that war was declared"; "the grounds for their declaration" [syn: ground]
2 an explanation of the cause of some phenomenon; "the reason a steady state was never reached was that the back pressure built up too slowly"
3 the capacity for rational thought or inference or discrimination; "we are told that man is endowed with reason and capable of distinguishing good from evil" [syn: understanding, intellect]
4 the state of having good sense and sound judgment; "his rationality may have been impaired"; "he had to rely less on reason than on rousing their emotions" [syn: rationality, reasonableness]
5 a justification for something existing or happening; "he had no cause to complain"; "they had good reason to rejoice" [syn: cause, grounds]
6 a fact that logically justifies some premise or conclusion; "there is reason to believe he is lying"


1 decide by reasoning; draw or come to a conclusion; "We reasoned that it was cheaper to rent than to buy a house" [syn: reason out, conclude]
2 present reasons and arguments [syn: argue]
3 think logically; "The children must learn to reason"

User Contributed Dictionary



From Anglo-Norman resoun ( raison), from rationem (accusative of ratio).


  • /ˈɹiːzn/, /"ri:zn/
  • Rhymes: -iːzən
  • Hyphenation: rea·son


  1. A thought or a consideration offered in support of a determination or an opinion; a just ground for a conclusion or an action; that which is offered or accepted as an explanation; the efficient cause of an occurrence or a phenomenon; a motive for an action or a determination; proof, more or less decisive, for an opinion or a conclusion; principle; efficient cause; final cause; ground of argument.
    He had no reason to do that.
  2. The mind, the reasoning processes of the mind.
    Mankind should develop reason above all other virtues.
  3. Due exercise of the reasoning faculty; accordance with, or that which is accordant with and ratified by, the mind rightly exercised; right intellectual judgment; clear and fair deductions from true principles; that which is dictated or supported by the common sense of mankind; right conduct; right; propriety; justice.
    I was promised, on a time, To have reason for my rhyme. —Spenser
  4. In the context of "mathematics|obsolete": ratio; proportion.



A thought or a consideration
The faculty of capacity of the human mind
Due exercise of the reasoning faculty


  1. To exercise the rational faculty; to deduce inferences from premises; to perform the process of deduction or of induction; to ratiocinate; to reach conclusions by a systematic comparison of facts.
  2. Hence: To carry on a process of deduction or of induction, in order to convince or to confute; to formulate and set forth propositions and the inferences from them; to argue.
  3. To converse; to compare opinions.
  4. To arrange and present the reasons for or against; to examine or discuss by arguments; to debate or discuss.
    I reasoned the matter with my friend.
  5. transitive rare To support with reasons, as a request.
  6. To persuade by reasoning or argument.
    to reason one into a belief; to reason one out of his plan
  7. To overcome or conquer by adducing reasons; — with down.
    to reason down a passion
  8. To find by logical process; to explain or justify by reason or argument; — usually with out.
    to reason out the causes of the librations of the moon''


To exercise the rational faculty
To carry on a process of deduction or of induction
checktrans-top transitive

Extensive Definition

globalize article Reason is a way of thinking characterized by logic, analysis, and synthesis. It is often contrasted with emotionalism, which is thinking driven by desire, passion or prejudice. Reason attempts to discover what is true or what is best. Reason often follows a chain of cause and effect, and the word "reason" can be a synynom for "cause". Reason has been a major subject of interest since the beginning of philosophy. Discussion about reason especially concerns:
  • its origin
  • its relationship to other related concepts such as language, logic, and consciousness
  • its ability to help people decide what is true
The question of whether or not animals can reason has been a subject of lively debate.
The concept of reason is closely related to the concept of language, as reflected in the meanings of the Greek word "logos", the root of logic, which translated into Latin became "ratio" and then in French "raison", from which the English word "reason" was derived.

Reason and logic

Reason is a type of thought. Logic is the attempt to make explicit the rules by which reason operates. The oldest surviving writing to explicitly and at length consider the rules by which reason operates are the works of the Greek philosopher Aristotle, especially Prior Analysis and Posterior Analysis. Although the Ancient Greeks had no separate word for logic as distinct from language and reason, Aristotle's neologism "syllogism" (syllogismos) identified logic clearly for the first time as a distinct field of study. When Aristotle referred to "the logical" (logos), he was referring more broadly to rational thought.
Reason and logic can be thought of as distinct, although logic is one important aspect of reason. Author Douglas Hofstadter, in Gödel, Escher, Bach, characterizes the distinction in this way. Logic is what is done "inside the system" by formal steps such as deduction. Reason is what is done "outside the system" by such informal methods as skipping steps, working backward, drawing diagrams, looking at examples, or seeing what happens if you change the rules of the system. In the present day there is an increasing tendency to use the terms interchangeably, or to see logic as the most pure or the defining form of reason.
Neurologist Terrence Deacon, following the tradition of Charles Peirce, has recently given a useful new description of what makes reason distinctive compared to logic, as well as the information processing of computers and at least most animals, in modern terms. Like many philosophers in the English tradition, such as Hobbes, Locke, and Hume, Peirce starts by distinguishing the type of thinking which is most essential to human reason as a type of associative thinking. Reason, by his account, requires associating perceptions with icons. For example, the mind may associate the image (or icon) of smoke with not only the image of fire, but may also associate the word "smoke", or indeed any made-up symbol, with the image of fire.

Reason, truth, and “first principles”

In western philosophy, reason has a twofold history. In classical times a conflict developed between the Platonists and the Aristotelians concerning the role of reason in confirming truth.
Both Aristotle and Plato considered this question. On the one hand, people use logic, deduction, and induction to reach conclusions they think are true. Conclusions reached in this way are considered more certain than basic sense perceptions. On the other hand, if such reasoned conclusions are only built upon sense perceptions, then our most logical conclusions can never be said to be certain because they are built upon the very same fallible perceptions they seek to better.
This leads to the question of first principles. Empiricism (associated with Aristotle and, more recently, with British philosophers such as John Locke and David Hume) asserts that sensory impressions are primary. Idealism, (associated with Plato and his school), claims that there is a "higher" reality, from which certain people can directly arrive at truth without the need of the senses, and that this higher reality is the primary source of truth.
In Greek, “first principles” are arkhai, starting points, and the faculty used to perceive them is sometimes referred to in Aristotle and Plato as “nous” which was close in meaning to “awareness” or “consciousness”.
Among those who would argue that reason can not be based upon experience alone, at least two major strands might be discerned. On the one hand, philosophers such as Plato, Aristotle, Alfarabi, Avicenna, Averroes, Maimonides, Aquinas and Hegel are sometimes said to have argued that reason must be fixed and discoverable - perhaps by dialectic, analysis, or study. In the vision of these thinkers, reason is divine or at least has divine attributes. Such an approach allowed religious philosophers such as Thomas Aquinas and Étienne Gilson to try to show that reason and revelation are compatable.
On the other hand, since the Seventeenth Century rationalists, reason has often been taken to be a subjective faculty, or rather the unaided ability (pure reason) to form concepts. For Descartes, Spinoza and Leibniz, this was associated with significant developments in mathematics. Kant attempted to show that pure reason could form concepts (time and space) that are the conditions of experience. Kant made his argument in opposition to Hume, who denied that reason had any role to play in experience.

Reason, language and mimesis

The recent writings of Deacon and Donald fit into an older tradition which makes reason connected to language, and mimesis, but more specifically the ability to create language as part of an internal modelling of reality specific to humankind. Other results are consciousness, and imagination or fantasy.
Thomas Hobbes describes the creation of “Markes, or Notes of remembrance” (Leviathan Ch.4) as “speech” (allowing by his definition that it is not necessarily a means of communication or speech in the normal sense; he was presumably thinking of "speech" as an English version of "logos" in this description). In the context of a language, these marks or notes are called "Signes" by Hobbes.
David Hume, following John Locke (and Berkeley), who followed Hobbes, emphasized the importance of associative thinking.
Concerning mimesis and fantasy being important in defining reason, see for example Aristotle's Poetics, De Anima, On Dreams, and On Memory and Recollection (and for example the Introduction by Michael Davis, printed with the 2002 translation by him and Seth Benardete of the Poetics), Jacob Klein’s A Commentary on the Meno Ch.5, and Tolkien's essay "On Fairy Stories".
In more recent times, important areas of research include the relationship between reason and language, especially in discussions of origin of language. Modern proponents of a priori reasoning, at least with regards to language, include Noam Chomsky and Steven Pinker, to whom Merlin Donald and Terrence Deacon can be usefully contrasted.

Reason and emotion or passion

In western literature, reason is often opposed to emotions or feelings -- desires, fears, hates, drives, or passions. Even in everyday speech, westerners tend to say for example that their passions made them behave contrary to reason, or that their reason kept the passions under control. Many writers, such as Nikos Kazantzakis, extol passion and disparage reason.
It is also common, particularly since Freud, to describe reason as the servant of the passions - the means of sorting out our desires and then getting what we want, or perhaps even the slave of the passions - allowing us to pretend to reason to the object of our desire. Such feigned reason is called "rationalization".
Philosophers such as Plato, Rousseau, Hume, and Nietzsche have combined both views - making rational thinking not only a tool of desires, but also something privileged within the spectrum of desires, being itself desired, and not only because of its usefulness in satisfying other desires.
Modern psychology has much to say on the role of emotions in belief formation. Deeper philosophical questions about the relation between belief and reality are studied in the field of epistemology, which forms part of the philosophical basis of science, a branch of human activity that specifically aims to determine (certain types of) truth by methods that avoid dependence on the emotions of the researchers.

Reason and faith, especially in the “Greater West”

In theology, reason, as distinguished from faith, is the human critical faculty exercised upon religious truth whether by way of discovery or by way of explanation. Some commentators have claimed that Western civilization can be almost defined by its serious testing of the limits of tension between “unaided” reason and faith in "revealed" truths - figuratively summarised as Athens and Jerusalem, respectively. Leo Strauss spoke of a "Greater West" which included all areas under the influence of the tension between Greek rationalism and Abrahamic revelation, including the Muslim lands. He was particularly influenced by the great Muslim philosopher Al-Farabi. In order to consider to what extent Eastern philosophy might have partaken of these important tensions, it is perhaps best to consider whether dharma or tao may be equivalent to Nature (by which we mean physis in Greek).
The limits within which reason may be used have been laid down differently in different churches and periods of thought: on the whole, modern religion tends to allow to reason a wide field, reserving, however, as the sphere of faith the ultimate (supernatural) truths of theology.
portalpar Logic
reason in Arabic: عقل (فلسفة)
reason in Bulgarian: Разум
reason in Catalan: Raó
reason in Czech: Rozum
reason in Danish: Ræsonnere
reason in German: Vernunft
reason in Estonian: Mõistus
reason in Modern Greek (1453-): Λογική
reason in Spanish: Razón (filosofía)
reason in Esperanto: Racio
reason in Persian: عقل
reason in French: Raison
reason in Korean: 이성
reason in Interlingua (International Auxiliary Language Association): Ration
reason in Italian: Ragione
reason in Latvian: Prāts
reason in Dutch: Rede
reason in Japanese: 理性
reason in Polish: Rozum
reason in Portuguese: Razão
reason in Quechua: Humu
reason in Russian: Разум
reason in Albanian: Arsyeja
reason in Serbian: Разум
reason in Finnish: Järki
reason in Swedish: Förnuft
reason in Vietnamese: Lý tính
reason in Yiddish: סברה

Synonyms, Antonyms and Related Words

Vernunft, acceptable, accomplishment, account, admissibility, advise with, aim, air, allegorization, ambition, analyze, answer, antecedent, apologia, apology, apply reason, argument, argumentum, ascertainment, aspiration, balance, bargain, basis, because of, brain, brains, by reason of, by virtue of, calculate, call, call in, calling, canvass, case, cause, cerebrate, clarification, clearing up, cogitate, collect, collogue, comment upon, common sense, compare notes, conceive, conception, conceptualize, conclude, confer, confer with, cons, consider, consideration, consult, consult with, contact with reality, controvert, convince, cool head, coolheadedness, coolness, counsel, cracking, deal with, debate, decipherment, decoding, deduce, deduction, deductive reasoning, defence, deliberate, deliberate upon, demonstration, demythologization, denouement, derive, determinant, determination, discourse, discourse about, discourse of reason, discursive reason, discuss, discuss with, disentanglement, dissuade, draw a conclusion, draw an inference, due sense of, due to, editing, elenchus, elucidation, emendation, end, end result, enlightenment, entertain ideas, esprit, estimate, euhemerism, examine, exchange observations, exchange views, excuse, exegesis, exemplification, exercise the mind, explanation, explication, exposition, expounding, extract, fetch, figure out, find, finding, finding-out, fitting, form ideas, foundation, gather, generalize, glean, go into, goal, good reason, good sense, gray matter, ground, grounds, guiding light, guiding star, handle, have conversations, head, headpiece, healthy mind, hold conference, horse sense, hypothesize, ideal, ideate, ignoratio elenchi, illumination, illustration, induce, induction, inductive reasoning, infer, inference, insight, inspiration, intellect, intellection, intellectual faculty, intellectualize, intelligence, intention, interpretation, investigate, issue, judgement, justifiability, justifiable, justification, justness, knock around, level head, levelheadedness, light, lodestar, logic, logical thought, logicality, logicalize, logicalness, logicize, lucid interval, lucidity, mainspring, marbles, material basis, matter, mens, mental balance, mental capacity, mental equilibrium, mental health, mental hygiene, mental poise, mentality, mind, motive, negotiate, normalcy, normality, normalness, nous, object, objective, occasion, on account of, outcome, owing to, palaver, parley, pass under review, percipience, perspicacity, persuade, philosophize, philosophy, plaidoyer, plain sense, plausibility, plea, plead with, pleading, point, power of reason, powwow, practical mind, practical wisdom, practicality, pretense, pretext, prevail upon, principle, proof, proper, pros, pros and cons, provide a rationale, psyche, purpose, put heads together, rap, ratio, ratiocination, rational, rational ground, rationale, rationalism, rationality, rationalization, rationalize, rationalizing, reason about, reason for, reason that, reason the point, reason why, reason with, reasonability, reasonable, reasonableness, reasoning, reasoning faculty, reckon, refer to, reflect, refutation, resolution, resolving, result, review, riddling, right, right mind, sake, sanemindedness, saneness, sanity, score, sense, senses, sensible, sensibleness, sift, simplification, sit down together, sit down with, smarts, sober senses, sober-mindedness, soberness, sobriety, solution, solving, sophistry, sorting out, sound mind, sound sense, soundness, soundness of mind, source, special pleading, specious reasoning, speculate, spring, stated cause, study, substance, sweet reason, syllogize, take as proved, take counsel, take up, take up with, talk, talk about, talk of, talk over, talking point, the big idea, the idea, the whatfor, the wherefore, the why, theorize, think, thresh out, treat, ulterior motive, underlying reason, understanding, unlocking, unraveling, unriddling, unscrambling, unspinning, untangling, untwisting, unweaving, upshot, urge, use reason, ventilate, vindication, vocation, warrant, wherefore, wholesomeness, why, whyfor, wit, work out, working, working-out
Privacy Policy, About Us, Terms and Conditions, Contact Us
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2
Material from Wikipedia, Wiktionary, Dict
Valid HTML 4.01 Strict, Valid CSS Level 2.1