What is the law of syllogism?

author

Syllogism is deduction. Two propositions (sentences affirming or denying something), called "major premise" and "minor premise", are followed by a conclusion. [change] Example 1. Man is a rational animal (major premise) 2. Aristotle is a man (minor premise) 3. Aristotle is a rational animal (conclusion). Aristotle studied different syllogisms and identified valid syllogisms as syllogisms with conclusion true if both premises are true. The example above is valid syllogism. Retrieved from "http://simple.wikipedia.org/wiki/Syllogism" http://simple.wikipedia.org/wiki/Syllogism Oct 13 08, 6:49 PM

Baloo55th

You do have to be careful with it, though: 1. Dogs have four paws. 2. Tiddles has four paws. 3. Therefore, Tiddles is a dog. Miaaoooouuuuuwwwwwww! Oct 14 08, 6:17 AM

looney_tunes

A valid syllogism is best identified if the premises are rephrased into implications. A valid syllogism has the structure: A implies B; B implies C; Therefore A implies C. Restating Author's example, you have Aristotle implies man; Man implies rational animal; Therefore Aristotle is a rational animal. Baloo's has the form A implies B; C implies B; from this start no valid conclusion can be drawn about a relationship between A and C. Oct 14 08, 1:40 PM

Baloo55th

It's actually based on one of Lewis Carroll's. For more: http://www.lewiscarroll.org/logic.html Oct 14 08, 2:22 PM

looney_tunes

The link provided to Lewis Carrol's logic puzzles has further links that explain the logic notation I yused above, as well as another to another technique: "A much easier way to do it, however, once you get the hang of the notation, is the Sommers-Englebretsen term logic," which looks more like algebra than traditional logic. Oct 15 08, 1:59 AM