[1] : The Collaborative International Dictionary of English v.0.48

syllogism \syl"logism\, n. oe. silogisme, of. silogime,
   sillogisme, f. syllogisme, l. syllogismus, gr. syllogismo`s a
   reckoning all together, a reasoning, syllogism, fr.
   syllogi`zesqai to reckon all together, to bring at once
   before the mind, to infer, conclude; sy`n with, together +
   logi`zesqai to reckon, to conclude by reasoning. see syn-,
   and logistic, logic. logic
   the regular logical form of every argument, consisting of
   three propositions, of which the first two are called the
   premises, and the last, the conclusion. the conclusion
   necessarily follows from the premises; so that, if these are
   true, the conclusion must be true, and the argument amounts
   to demonstration;

   note: as in the following example:
         1913 webster every virtue is laudable; kindness is a
         virtue; therefore kindness is laudable.
         1913 webster these propositions are denominated
         respectively the major premise, the minor premise, and
         the conclusion.
         1913 webster

   note: if the premises are not true and the syllogism is
         regular, the reasoning is valid, and the conclusion,
         whether true or false, is correctly derived.
         1913 webster syllogistic
see also:
syn- logistic logic 

[2] : WordNet (r) 2.0

syllogism
     n : deductive reasoning in which a conclusion is derived from
         two premises

[3] : Moby Thesaurus II by Grady Ward, 1.0

32 moby thesaurus words for "syllogism":
   aristotelian sorites, baconian method, goclenian sorites,
   a fortiori reasoning, a posteriori reasoning, a priori reasoning,
   analysis, categorical syllogism, deduction, deductive reasoning,
   dilemma, enthymeme, epagoge, figure, generalization,
   hypothesis and verification, induction, inductive reasoning,
   inference, mode, modus tollens, mood, paralogism,
   particularization, philosophical induction, prosyllogism,
   pseudosyllogism, rule, rule of deduction, sorites,
   syllogistic reasoning, synthesis

[4] : THE DEVIL'S DICTIONARY ((C)1911 Released April 15 1993)

syllogism, n.  a logical formula consisting of a major and a minor
assumption and an inconsequent.  see logic.

Syllogism >> S Words
Syllogism, definition of term: Syllogism
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