Understanding Toulmin Logic

Another way of describing the structure of argument was introduced by the philosopher Stephen Toulmin in his book The Uses of Argument (1958). Toulmin observed that although formal logic is effective for analyzing classical arguments, it is inadequate for describing the arguments you encounter in everyday life. Although Toulmin was primarily concerned with the structures of arguments at the level of sentences or paragraphs, his model is also useful when dealing with longer arguments.

In its simplest terms, a Toulmin argument has three parts—the claim, the grounds, and the warrant. The claim is the main point of the essay—usually stated as the thesis. The grounds are the evidence that a writer uses to support the claim. The warrant is the inference—either stated or implied—that connects the claim to the grounds.

200

A basic argument using Toulmin logic would have the following structure.

CLAIM Online education should be a part of all students’ education.
GROUNDS Students who take advantage of online education get better grades and report less stress than students who do not.
WARRANT Online education is a valuable educational option.

Notice that the three-part structure above resembles the syllogism that is the backbone of classical argument. (See Chapter 5 for a discussion of syllogisms.)

NOTE

When you use Toulmin logic to construct an argument, you still use deductive and inductive reasoning. You arrive at your claim inductively from facts, observations, and examples, and you connect the grounds and the warrant to your claim deductively.