In traditional logic, a syllogism is an inference in which one proposition (the conclusion) follows of necessity from two others (known as premises).
The definition is traditional, but is derived loosely from Aristotle's Prior Analytics, Book I, c. 1. The Greek sullogismos means "deduction".
Forms of syllogism:
- Categorical syllogism
- Disjunctive syllogism
- Hypothetical syllogism
- add list of other syllogism forms here
- If all humans (B's) are mortal (A),
- and all Greeks (C's) are humans (B's),
- then all Greeks (C's) are mortal (A).
- Men die.
- Socrates is a man.
- Socrates will die.
- Grass dies.
- Men die.
- Men are grass.
Epagoge are weak syllogisms that rely on inductive reasoning.
See also: Venn diagram