REASON, n. re'zn. [L. ratio, which is from ratus, and which proves reor to be contracted from redo, redor, and all unite with rod, L. radius, &c. Gr. to say or speak, whence rhetoric. See Read.]

1. That which is thought or which is alledged in words, as the ground or cause of opinion, conclusion or determination. I have reasons which I may choose not to disclose. You ask me my reasons. I freely give my reasons. The judge assigns good reasons for his opinions, reasons which justify his decision. Hence in general,
2. The cause, ground, principle or motive of any thing said or done; that which supports or justifies a determination, plan or measure. Virtue and vice are not arbitrary things; but there is a natural and eternal reason for that goodness and virtue, and against vice and wickedness. – 1 Pet iii. Tillotson.
3. Efficient cause. He is detained by reason of sickness. Spain is thin sown of people, partly by reason of its sterility of soil. – Bacon. The reason of the motion of the balance in a wheel-watch is by motion of the next wheel. – Hale.
4. Final cause. Reason, in the English language, is sometimes taken for true and clear principles; sometimes for clear and fair deductions; sometimes for the cause, particularly the final cause. – Locke.
5. A faculty of the mind by which it distinguishes truth from falsehood, and good from evil, and which enables the possessor to deduce inferences from facts or from propositions. – Encyc. Self-love, the spring of motion, acts the soul, / Reason's comparing balance rules the whole. / That sees immediate good by present sense, / Reason the future and the consequence. – Pope. Reason is the director of man's will. – Hooker.
6. Ratiocination; the exercise of reason. But when by reason she the truth has found. Davies.
7. Right; justice; that which is dictated or supported by is reason. Every man claims to have reason on his side. I was promised on a time / To have reason for my rhyme. – Spenser.
8. Reasonable claim; justice. God brings good out of evil, and therefore it were but reason we should trust God to govern his own world. – Taylor.
9. Rationale; just account. This reason did the ancient fathers render, why the church was called Catholic. – Pearson. [See No. 1 and 2.]
10. Moderation; moderate demands; claims which reason and justice admit or prescribe. The most probable way of bringing France to reason, would be by the making an attempt on the Spanish West Indies. – Addison. In reason, in all reason, in justice; with rational ground. When any thing is proved by as good arguments as a thing of that kind is capable of, we ought not in reason to doubt its existence. – Tillotson.

1. To exercise the faculty of reason; to deduce inference justly from premises. Brutes do not reason; children reason imperfectly.
2. To argue; to infer conclusions from premises, or to deduce new or unknown propositions from previous propositions which are known or evident. To reason justly, is to infer from propositions which are known, admitted or evident the conclusions which are natural, or which necessarily result from them. Men may reason within themselves; they may reason before a court or legislature; they may reason wrong as well as right.
3. To debate; to confer or inquire by discussion or mutual communication of thoughts, arguments, or reasons. And they reasoned among themselves. – Matth. xvi. To reason with, to argue with; to endeavor to inform, convince or persuade by argument. Reason with a profligate son, and if possible, persuade him of his errors. #2. To discourse; to talk; to take or give an account. Stand still, that I may reason with you before the Lord, of all the righteous acts of the Lord. [Obs.] – 1 Sam. xii.

1. To examine or discuss by arguments; to debate or discuss. I reasoned the matter with my friend. When they are clearly discovered, well digested and well reasoned in every part, there is beauty in such a theory. – Burnet.
2. To persuade by reasoning or argument; as, to reason one into a belief of truth; to reason one out of his plan; to reason down a passion.

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.
   
   

   I 'll give him reasons for it. Shak.

   The reason of the motion of the balance in a wheel watch is by the motion of the next wheel. Sir M. Hale.

   This reason did the ancient fathers render, why the church was called "catholic." Bp. Pearson.

   Virtue and vice are not arbitrary things; but there is a natural and eternal reason for that goodness and virtue, and against vice and wickedness. Tillotson.

2. 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.
3. To arrange and present the reasons for or against; to examine or discuss by arguments; to debate or discuss; as, I reasoned the matter with my friend.
   
   

   When they are clearly discovered, well digested, and well reasoned in every part, there is beauty in such a theory. T. Burnet.

4. The faculty or capacity of the human mind by which it is distinguished from the intelligence of the inferior animals; the higher as distinguished from the lower cognitive faculties, sense, imagination, and memory, and in contrast to the feelings and desires. Reason comprises conception, judgment, reasoning, and the intuitional faculty. Specifically, it is the intuitional faculty, or the faculty of first truths, as distinguished from the understanding, which is called the discursive or ratiocinative faculty.
   
   

   We have no other faculties of perceiving or knowing anything divine or human, but by our five senses and our reason. P. Browne.

   In common and popular discourse, reason denotes that power by which we distinguish truth from falsehood, and right from wrong, and by which we are enabled to combine means for the attainment of particular ends. Stewart.

   Reason is used sometimes to express the whole of those powers which elevate man above the brutes, and constitute his rational nature, more especially, perhaps, his intellectual powers; sometimes to express the power of deduction or argumentation. Stewart.

   By the pure reason I mean the power by which we become possessed of principles. Coleridge.

   The sense perceives; the understanding, in its own peculiar operation, conceives; the reason, or rationalized understanding, comprehends. Coleridge.

5. 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.
   
   

   Stand still, that I may reason with you, before the Lord, of all the righteous acts of the Lord. 1 Sam. xii. 7.

6. To support with reasons, as a request.
   
   
   [R.] Shak.
7. 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.

   But law in a free nation hath been ever public reason; the enacted reason of a parliament, which he denying to enact, denies to govern us by that which ought to be our law; interposing his own private reason, which to us is no law. Milton.

   The most probable way of bringing France to reason would be by the making an attempt on the Spanish West Indies. Addison.

8. To converse; to compare opinions.
   
   
   Shak.
9. To persuade by reasoning or argument; as, to reason one into a belief; to reason one out of his plan.
   
   

   Men that will not be reasoned into their senses. L'Estrange.

10. Ratio; proportion.
    
    
    [Obs.] Barrow.

    By reason of, by means of; on account of; because of. "Spain is thin sown of people, partly by reason of the sterility of the soil." Bacon. -- In reason, In all reason, in justice; with rational ground; in a right view.

    When anything is proved by as good arguments as a thing of that kind is capable of, we ought not, in reason, to doubt of its existence. Tillotson.

    -- It is reason, it is reasonable; it is right. [Obs.]

    Yet it were great reason, that those that have children should have greatest care of future times. Bacon.

    Syn. -- Motive; argument; ground; consideration; principle; sake; account; object; purpose; design. See Motive, Sense.

11. To overcome or conquer by adducing reasons; -- with down; as, to reason down a passion.
12. To find by logical processes; to explain or justify by reason or argument; -- usually with out; as, to reason out the causes of the librations of the moon.