reason

[ree-zuh n] /ˈri zən/
noun
1.
a basis or cause, as for some belief, action, fact, event, etc.:
the reason for declaring war.
2.
a statement presented in justification or explanation of a belief or action.
3.
the mental powers concerned with forming conclusions, judgments, or inferences.
4.
sound judgment; good sense.
5.
normal or sound powers of mind; sanity.
6.
Logic. a premise of an argument.
7.
Philosophy.
  1. the faculty or power of acquiring intellectual knowledge, either by direct understanding of first principles or by argument.
  2. the power of intelligent and dispassionate thought, or of conduct influenced by such thought.
  3. Kantianism. the faculty by which the ideas of pure reason are created.
verb (used without object)
8.
to think or argue in a logical manner.
9.
to form conclusions, judgments, or inferences from facts or premises.
10.
to urge reasons which should determine belief or action.
verb (used with object)
11.
to think through logically, as a problem (often followed by out).
12.
to conclude or infer.
13.
to convince, persuade, etc., by reasoning.
14.
to support with reasons.
Idioms
15.
bring (someone) to reason, to induce a change of opinion in (someone) through presentation of arguments; convince:
The mother tried to bring her rebellious daughter to reason.
16.
by reason of, on account of; because of:
He was consulted about the problem by reason of his long experience.
17.
in / within reason, in accord with reason; justifiable; proper:
She tried to keep her demands in reason.
18.
stand to reason, to be clear, obvious, or logical:
With such an upbringing it stands to reason that the child will be spoiled.
19.
with reason, with justification; properly:
The government is concerned about the latest crisis, and with reason.
Origin
1175-1225; Middle English resoun, reisun (noun) < Old French reisun, reson < Latin ratiōn- (stem of ratiō) ratio
Related forms
reasoner, noun
nonreason, noun
nonreasoner, noun
outreason, verb (used with object)
subreason, noun
Synonyms
1. purpose, end, aim, object, objective. Reason, cause, motive are terms for a circumstance (or circumstances) which brings about or explains certain results. A reason is an explanation of a situation or circumstance which made certain results seem possible or appropriate: The reason for the robbery was the victim's display of his money. The cause is the way in which the circumstances produce the effect, that is, make a specific action seem necessary or desirable: The cause was the robber's extreme need of money. A motive is the hope, desire, or other force which starts the action (or an action) in an attempt to produce specific results: The motive was to get money to buy food for his family. 2. excuse, rationalization. 3. understanding, intellect, mind, intelligence. 10. persuade.
Usage note
The construction reason is because is criticized in a number of usage guides: The reason for the long delays was because the costs greatly exceeded the original estimates. One objection to this construction is based on its redundancy: the word because (literally, by cause) contains within it the meaning of reason; thus saying the reason is because is like saying “The cause is by cause,” which would never be said. A second objection is based on the claim that because can introduce only adverbial clauses and that reason is requires completion by a noun clause. Critics would substitute that for because in the offending construction: The reason for the long delays in completing the project was that the costs. … Although the objections described here are frequently raised, reason is because is still common in almost all levels of speech and occurs often in edited writing as well.
A similar charge of redundancy is made against the reason why, which is also a well-established idiom: The reason why the bill failed to pass was the defection of three key senators.
Examples from the web for reason
  • The need for water droplets and strong sunlight is the reason rainbows are often observed after rain.
  • Self-medication may be the reason the blogosphere has taken off.
  • And with good reason: they represent a valuable source of protein and fat.
  • One reason is a phenomenon called feedback-as galaxies accrete matter, they also spew gas back out into space.
  • My grandfather, for some reason, wore a hat to meals.
  • The rider, who embodies reason, attempts to steer the giant beast by concocting justifications for the new course.
  • It stands to reason that this develops sensitivity of hearing.
  • But this trait isn't the only reason scientists look to fruit flies for clues about how memories form in humans.
  • Part of the reason is that it is closely tied to our emotions.
  • The official reason is that it's a fascinating biologically derived material that isn't biodegradable.
British Dictionary definitions for reason

reason

/ˈriːzən/
noun
1.
the faculty of rational argument, deduction, judgment, etc
2.
sound mind; sanity
3.
a cause or motive, as for a belief, action, etc
4.
an argument in favour of or a justification for something
5.
(philosophy) the intellect regarded as a source of knowledge, as contrasted with experience
6.
(logic) grounds for a belief; a premise of an argument supporting that belief
7.
by reason of, because of
8.
in reason, within reason, within moderate or justifiable bounds
9.
it stands to reason, it is logical or obvious: it stands to reason that he will lose
10.
listen to reason, to be persuaded peaceably
11.
reasons of State, political justifications for an immoral act
verb
12.
(when transitive, takes a clause as object) to think logically or draw (logical conclusions) from facts or premises
13.
(intransitive) usually foll by with. to urge or seek to persuade by reasoning
14.
(transitive) often foll by out. to work out or resolve (a problem) by reasoning
Derived Forms
reasoner, noun
Usage note
The expression the reason is because… should be avoided. Instead one should say either this is because… or the reason is that…
Word Origin
C13: from Old French reisun, from Latin ratiō reckoning, from rērī to think
Word Origin and History for reason
n.

c.1200, "intellectual faculty that adopts actions to ends," also "statement in an argument, statement of explanation or justification," from Anglo-French resoun, Old French raison "course; matter; subject; language, speech; thought, opinion," from Latin rationem (nominative ratio) "reckoning, understanding, motive, cause," from ratus, past participle of reri "to reckon, think," from PIE root *re(i)- "to reason, count" (cf. Old English rædan "to advise; see read (v.)).

Meaning "sanity; degree of intelligence that distinguishes men from brutes" is recorded from late 13c. Sense of "grounds for action, motive, cause of an event" is from c.1300. Middle English sense of "meaning, signification" (early 14c.) is in the phrase rhyme or reason. Phrase it stands to reason is from 1630s. Age of Reason "the Enlightenment" is first recorded 1794, as the title of Tom Paine's book.

v.

early 14c., resunmen, "to question (someone)," also "to challenge," from Old French raisoner "speak, discuss; argue; address; speak to," from Late Latin rationare "to discourse," from ratio (see reason (n.)). Intransitive sense of "to think in a logical manner" is from 1590s; transitive sense of "employ reasoning (with someone)" is from 1847. Related: Reasoned; reasoning.

Idioms and Phrases with reason

reason

see:
Encyclopedia Article for reason

rationality

in philosophy, the faculty or process of drawing logical inferences. The term "reason" is also used in several other, narrower senses. Reason is in opposition to sensation, perception, feeling, desire, as the faculty (the existence of which is denied by empiricists) by which fundamental truths are intuitively apprehended. These fundamental truths are the causes or "reasons" of all derivative facts. According to the German philosopher Immanuel Kant, reason is the power of synthesizing into unity, by means of comprehensive principles, the concepts that are provided by the intellect. That reason which gives a priori principles Kant calls "pure reason," as distinguished from the "practical reason," which is specially concerned with the performance of actions. In formal logic the drawing of inferences (frequently called "ratiocination," from Latin ratiocinari, "to use the reasoning faculty") is classified from Aristotle on as deductive (from generals to particulars) and inductive (from particulars to generals).

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