See cause, cause of. Reason appears in numerous trite expressions such as "It stands to reason," "theirs not to reason why," "within reason," "by reason of," "bring someone to reason," and "any reasonable person." Note that one word, because, can replace five words: "for the simple reason that." If one overuses reason by itself, he can try understanding, intuition, judgment, or discernment. In the sense of "cause" or "basis for action," occasionally substitute purpose, motive, end, object, or objective.
Dictionary of problem words and expressions. Harry Shaw. 1975.