Noun

(en noun)

A cause:

# That which causes something: an efficient cause, a proximate cause.

#* 1996 , (w), : Evolution and the Meanings of Life , page 198:

There is a reason why so many should be symmetrical: The selective advantage in a symmetrical complex is enjoyed by all the subunits

# A motive for an action or a determination.

#* 1806 , Anonymous, Select Notes to Book XXI, in, (Alexander Pope), translator, The (Odyssey) of (Homer) , volume 6 (London, F.J. du Roveray), page 37:

This is the reason why he proposes to offer a libation, to atone for the abuse of the day by their diversions.

#* 1881 , (Henry James), (The Portrait of a Lady) , chapter 10:

Ralph Touchett, for reasons best known to himself, had seen fit to say that Gilbert Osmond was not a good fellow

# An excuse: a thought or a consideration offered in support of a determination or an opinion; that which is offered or accepted as an explanation.

#* 1966 , (Graham Greene), ((Penguin Classics) edition, ISBN 0140184945), page 14:

I have forgotten the reason' he gave for not travelling by air. I felt sure that it was not the correct ' reason , and that he suffered from a heart trouble which he kept to himself.

(label) Rational]] thinking (or the capacity for it; the cognitive [[faculty, faculties, collectively, of conception, judgment, deduction and intuition.

* 1970 , (Hannah Arendt), On Violence (ISBN 0156695006), page 62:

And the specific distinction between man and beast is now, strictly speaking, no longer reason (the lumen naturale of the human animal) but science

*{{quote-magazine, date=2014-06-21, volume=411, issue=8892, magazine=(The Economist)

, title= Magician’s brain , passage=The [Isaac] Newton that emerges from the [unpublished] manuscripts is far from the popular image of a rational practitioner of cold and pure reason . The architect of modern science was himself not very modern. He was obsessed with alchemy.}}

(label) Something reasonable, in accordance with thought; justice.

* (rfdate) (Edmund Spenser):

I was promised, on a time, To have reason for my rhyme.

Ratio; proportion.

(Barrow)

Noun

(en noun)

Subject; theme; a category or general area of interest.

*{{quote-magazine, date=2013-08-03, volume=408, issue=8847, magazine=(The Economist)

, title= The machine of a new soul , passage=The yawning gap in neuroscientists’ understanding of their topic is in the intermediate scale of the brain’s anatomy. Science has a passable knowledge of how individual nerve cells, known as neurons, work. It also knows which visible lobes and ganglia of the brain do what. But how the neurons are organised in these lobes and ganglia remains obscure. Yet this is the level of organisation that does the actual thinking—and is, presumably, the seat of consciousness.}}

(Internet) Discussion thread.

(obsolete) An argument or reason.

* Bishop Wilkins

contumacious persons, who are not to be fixed by any principles, whom no topics can work upon

(obsolete, medicine) An external local application or remedy, such as a plaster, a blister, etc.

(Wiseman)