• Major Premise: All men are mortal,
• Minor Premise: Socrates was a man,
• Conclusion: Socrates is mortal.

Toulmin realized that this form of argumentation is not what one encounters when listening to a public speech, arguing with a roommate about what music to listen to, or talking politics at a bar. Consequently, Toulmin developed his theory in order to explain how argumentation occurs in the natural process of everyday argument. Consequently, Toulmin wanted to explain how real people (not philosophers) argue.

Although Toulmin's position on formal logic -- that formal rules of logic do not fit well with common practices of argument -- may seem obvious, one must remember the time period in which Toulmin developed his theory. Students of public speaking, rhetoric, and logic were only taught formal logic. Using a contemporary example to illustrate: Students were taught how to program a computer before they were taught how to click a mouse. When one recognizes the traditions of the time period, Toulmin's theory of argument seems even more revolutionary.

The Toulmin Model of Argument-Basics

Claim: Think of the claim in an argument as the most general statement in the argument. It may not be a particularly general statement all by itself, and some claims for arguments are very narrow. But the claim in an argument is like the umbrella statement that all other parts of an argument have to fall under. If a reason (or evidence) doesn't fall under the umbrella of the claim, then it’s irrelevant.

Support: These are the reasons given in support of the claim; they are also known as evidence, proof, data, arguments, or grounds. The support of a claim can come in the form of facts and statistics, expert opinion, examples, explanations, and logical reasoning. You can find the support by asking, "What does the author say to persuade the reader of the claim?"

Warrants: These are the assumptions or presuppositions underlying the argument. Warrants are generally accepted beliefs and values, common ways our culture or society views things; because they are so commonplace, warrants are almost always unstated and implied. The author and audience may either share these beliefs, or the author’s warrants may be in conflict with audience’s generally held beliefs and cultural norms and values. Warrants are important because they are the "common ground" of author and audience; shared warrants invite the audience to participate by unconsciously supplying part of the argument. Warrants are also important because they provide the underlying reasons linking the claim and the support. You can infer the warrants by asking, "What’s causing the author to say the things s/he does?" or "Where’s the author coming from?"

Outline of the Toulmin Model

                                therefore
Data----------------------------Qualifier-----------Claim
             |                     |
             |                     |
             |                     |
             |                     |
             |                     |
             since                 unless
             Warrant---------------Rebuttal
             |
             |
             |
             |
             |
             because
             Backing
 

Illustration of the Model

                                therefore
Data----------------------------Qualifier-----------Claim
Russia has      |                  Probably            Russia would
violated 50      |                     |                      violate the
of 52 intl.        |                     |                      proposed ban
agreements     |                     |                     on nuclear
                      |                     |                     weapons
                 since                 unless               testing.
             Warrant---------------Rebuttal
           Past violations           The ban on nuclear
           are symptomatic        weapons testing is
           of probable future      significantly different
           violations                   from the violated
                         |                  agreements
                         |
                         |
                         |
                         |
                     because
                     Backing
             Other nations that had such
             a record of violations continued such
             action; Expert X states that nations that
             have been chronic violators nearly always
             continue such acts; etc.