Heinrichs introduces seven deadly logical sins. The first sin is false comparison, or examples being placed in incorrect categories. Political candidates often use this fallacy. For example, one candidate might say, “I’m a successful businessman. Elect me mayor and I’ll run a successful city” (168). Just because the candidate is a successful businessman does not mean he will have a successful political career. Business skills and political skills are not the same.

The second logical sin is the bad example. With this fallacy, persuaders use an incorrect or wrongly interpreted example in their argument (i.e., an example that fails to prove the argument’s conclusion). Hasty generalizations fall under this sin, such as: “That intern from Yale was great. Let’s get another Yalie” (171). Having one hardworking intern from Yale does not mean the next will prove the same.

The third logical sin is ignorance as proof. In this case, persuaders claim that a lack of examples support that something does not exist. Superstitions fall under this sin.

The fourth logical sin is tautology, which is when persuaders repeat something using different words. Heinrichs calls tautology “one of the most boring fallacies” (173) because it leads to the

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