The necessity of casuistry might, in fact, be deduced from the very origin, and genesis of the word. First came the general law or rule of action. This was like the major proposition of a syllogism. But next came a special instance or _case_, so stated as to indicate whether it did or did not fall under the general rule. This, again, was exactly the minor proposition in a syllogism. For example, in logic we say, as the major proposition in a syllogism, _Man is mortal_. This is the rule. And then 'subsuming' (such is the technical phrase--_subsuming_) Socrates under the rule by a minor proposition--viz. Socrates is a man--we are able mediately to connect him with the predicate of that rule, viz, _ergo_, Socrates is mortal.[Footnote: The ludicrous blunder of Reid (as first published by Lord Kames in his _Sketches_), and of countless others, through the last seventy or eighty years, in their critiques on the logic of Aristotle, has been to imagine that such illustrations of syllogism as these were meant for specimens of what syllogism could perform. What an elaborate machinery, it was said, for bringing out the merest self-evident truisms! But just as reasonably it might have been objected, when a mathematician illustrated the process of addition by saying 3+4=7, Behold what pompous nothings! These Aristotelian illustrations were _purposely_ drawn from cases not open to dispute, and simply as exemplifications of the meaning: they were intentionally self-evident.] Precisely upon this model arose casuistry. A general rule, or major proposition, was laid down--suppose that he who killed any human being, except under the palliations X, Y, Z, was a murderer. Then in a minor proposition, the special case of the suicide was considered. It was affirmed, or it was denied, that his case fell under some one of the palliations assigned. And then, finally, accordingly to the negative or affirmative shape of this minor proposition, it was argued, in the conclusion, that the suicide was or was not, a murderer. Out of these _cases_, i.e. oblique deflexions from the universal rule (which is also the grammarian's sense of the word _case_) arose _casuistry_.