The Rationale for Toulmin's Theory: Problems With Formal Logic

Toulmin developed his theory of argumentation because of what he viewed as an inherent problem with formal logic. Put simply, Toulmin recognized what every person should already know: Real people do not argue in syllogisms. You may remember from a philosophy class that a syllogism is a form of logical argument. According to rules of logic, if an audience accepts both the major and minor premises of a syllogism, they must accept the conclusions. For instance, many people are familiar with the following example of a syllogism:

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.

As you traverse this web site, keep in mind the thought that Toulmin developed his theory to apply in common argumentation situations. It may be helpful to think about arguments that you have engaged in and then apply Toulmin's theory to your own experiences.

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E-Mail the designers of the Toulmin Web Page: Charles Soukup and Scott Titsworth, Department of Communication Studies. This page was created as part of a class project in Educational Psychology 942. All material is copyrighted by the University of Nebraska. No portion of this may be used without the expressed written permission of the creators.