Syllogism is defined as logical reasoning where you arrive at a conclusion by looking at two other premises or ideas.(noun)
If you know all squares are rectangles and all rectangles are shapes, and you deduce from this that all squares are shapes; this is an example of syllogism.
See syllogism in Webster's New World College Dictionary
Origin: ME silogisme < MFr < L syllogismus < Gr syllogismos, a reckoning together < syllogizesthai, to reckon together, sum up < syn-, together + logizesthai, to reason < logos, word: see logic
See syllogism in American Heritage Dictionary 4
Origin: Middle English silogisme
Origin: , from Old French
Origin: , from Latin syllogismus
Origin: , from Greek sullogismos
Origin: , from sullogizesthai, to infer
Origin: : sun-, syn-
Origin: + logizesthai, to count, reckon (from logos, reason; see leg- in Indo-European roots).
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