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Book Review – The Fallacy Detective

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The Fallacy Detective, written by Hans and Nathaniel Bluedorn, is a book designed for teens or adults that teaches how to spot common errors in reasoning. The goals for this book are clearly laid out in the introduction. When the reader has completed this book he should be able to put a high value on good reasoning, know how to spot many forms of bad reasoning and know how to avoid using many fallacies in his own reasoning.

The authors provide a vision of Christian logic in which they appeal to the need for Christians to strive for a higher standard of reasoning, in order to attain greater ability in discernment. Logic is an important foundation for the science of discernment. Thus they seek to define good reasoning in a biblical way. “Logic is the science of thinking the way God thinks – the way Jesus taught us to think” (page 14).

The book contains thirty-six lessons which progress from the most common and basic fallacies, to statistical fallacies and even propaganda. All those terms I have not heard since my university Critical Thinking courses are present as well as some that are commonly used and misused: red herring, ad hominem, tu quoque, appeal to the people, part-to-whole, whole-to-part and so on. Each lesson is followed by several questions which allow the reader to apply what he has just learned. I was glad to see that the questions are cumulative, meaning that what has been taught in previous lessons is continually reviewed in the application questions for subsequent chapters.

The authors write in a style that will appeal to teens and young people. The text is interspersed with comics (such as Calvin & Hobbes, Peanunts and Dilbert) and anecdotes. It is also a funny book, as there are many places where the authors turn to humor to make the book enjoyable. A typical lesson may begin similar to this one, which discusses weak analogies: “Let’s say…you are a budding scientist wanting to write your graduate thesis on the long term effects of Pop-Tarts on humans. The only problem is, you can’t find enough people who are willing to eat thirty-four Pop-Tarts a day for one year” (page 131).

Can learning logic be fun? With The Fallacy Detective it appears that it can be. I thoroughly enjoyed this book and would recommend it to anyone who wants to improve his reasoning skills. While its primary usefulness will be for teenagers, adults will also enjoy it and benefit from the lessons. If you homeschool your children, this may be a useful title. You can read more about it at christianlogic.com.


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