Toulmin Model 2.0

Deductive reasoning (Betsy is a cow, all cows eat grass, therefore Betsy eats grass) is widely regarded as the most scientific and accurate form of logic. It says: “Here are some known facts. What can we learn from them?”

In debate, your position is already assigned. You already know what you’ve learned, now you just have to find some facts to support it. That’s inductive reasoning.

Model of Reasoning

Stephen Toulmin was a brilliant philosopher who developed a model for arguing moral ideas. Unlike abstract deductive syllogisms, Toulmin focused on how a specific argument can be proven or refuted. His invention, the Toulmin Model, was specifically designed for debate. Here’s a modified version that you can use every round.

Claim is the argument you’re trying to make. If the judge accepts your claim, that should help you. If it doesn’t help, the argument doesn’t belong in the round. Example: 

“Country life is peaceful.”

Ground (sometimes called “analysis”) is the logical foundation for the claim. It provides the reasoning for your argument, something that should make internal sense to the judge. Why is the claim true? Because of the grounds. 

“You have fewer things clamoring for attention.”

Warrant provides evidence: the external proof of your argument. It could prove the ground true, or connect the ground and claim together. 

“The population density in a rural area is a fraction of that of an urban area.”
“On average, people in the country live longer and suffer from less stress-related illnesses.”


Adopt the Format

While you won’t be using these terms constantly, every argument you run in debate should follow this basic format. Most don’t! For example, a policy debater might read a harm tag and then jump right into his evidence – without providing any logical explanation for his position.  A value debater might elaborate on a topic area without actually making a claim. A fact debater might contend something based on pure conjecture. 

Make sure your argumentation includes all three elements. If your opponent runs an argument that is missing something – for example, if he presents an empty claim with no supporting logic or evidence – you can jump on it with a response like “No Warrant.”