syllogism

[ sil-uh-jiz-uhm ]

noun

1. Logic. an argument the conclusion of which is supported by two premises, of which one major premise contains the term major term that is the predicate of the conclusion, and the other minor premise contains the term minor term that is the subject of the conclusion; common to both premises is a term middle term that is excluded from the conclusion. A typical form is “All A is C; all B is A; therefore all B is C.”
2. deductive reasoning.
3. an extremely subtle, sophisticated, or deceptive argument.

syllogism

/ ˈsɪləˌdʒɪzəm /

noun

1. a deductive inference consisting of two premises and a conclusion, all of which are categorial propositions. The subject of the conclusion is the minor term and its predicate the major term; the middle term occurs in both premises but not the conclusion. There are 256 such arguments but only 24 are valid. Some men are mortal; some men are angelic; so some mortals are angelic is invalid, while some temples are in ruins; all ruins are fascinating; so some temples are fascinating is valid. Here fascinating, in ruins, and temples are respectively major, middle, and minor terms
2. a deductive inference of certain other forms with two premises, such as the hypothetical syllogism, if P then Q; if Q then R; so if P then R
3. a piece of deductive reasoning from the general to the particular
4. a subtle or deceptive piece of reasoning

Word History and Origins

Origin of syllogism¹

1350–1400; < Latin syllogismus < Greek syllogismós, equivalent to syllog- ( syllogize ) + -ismos -ism; replacing Middle English silogime < Old French < Latin, as above

Word History and Origins

Origin of syllogism¹

C14: via Latin from Greek sullogismos, from sullogizesthai to reckon together, from sul- syn- + logizesthai to calculate, from logos a discourse

Example Sentences

Of course, “No means Yes” is a novel logical syllogism, but anything is possible.

From The Daily Beast

This seems like an example of my favorite policy syllogism: 1.

From The Daily Beast

There's a terrible syllogism that tends to follow on tragedies like this:   1.

From The Daily Beast

I thought I would be protected by historical precision, reputation, syllogism and sincerity.

From The Daily Beast

It is rarely the case in literature that the syllogism is fully stated: generally one of the premises is omitted.

From Project Gutenberg

If the major premise of this syllogism be granted, the conclusion is unquestionable.

From Project Gutenberg

However, if this were put into a syllogism, it would read as follows: All persons who do wrong pay the penalty soon.

From Project Gutenberg

Whatever can be proved at all can be reduced to a syllogism but agreement upon premises is in this case impossible.

From Project Gutenberg

But Aquinas, with his Aristotelian method of syllogism and definitions, could not go beyond Augustine.

From Project Gutenberg