The UVic Writer's Guide


Syllogisms


A syllogism is a means of breaking down an argument into three simple, related terms:

  1. All UVic students receive grades;
  2. I am a UVic student; therefore
  3. I receive grades.

There are three parts to a syllogistic argument. The major premise is the first, general statement: "All UVic students receive grades." The minor premise is the second, specific statement: "I am a UVic student." The conclusion is the logical resolution of the two premises: "I receive grades." To be an effective argument, both premises of the syllogism must be true, and they must also relate logically one to the other.

Arguments of this kind tend to fail because the general premise is not valid:

  1. All students like pizza.
  2. Hassan is a student, therefore
  3. Hassan likes pizza.

The assumption that all students like pizza is invalid (if nearly true).

Improperly used, the syllogism is a handy device for producing charmingly erroneous conclusions like this one:

  1. Slugs crawl on the ground;
  2. I can crawl on the ground; therefore
  3. I am a slug.

While this conclusion may be true in a metaphorical sense, it does not follow logically from the first two statements because the two premises are not logically connected.


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Copyright, The Department of English, University of Victoria, 1995
This page updated September 24, 1995