Big Brain Ideas

How to Read a Book, Chapter 6: Pigeonholing a Book

Key Ideas

The primary argument of Chapter 6 is that you have to know what kind of book you’re reading to get the most out of it. Adler recommends classifying the book before you start reading. Is it fiction or non-fiction? Is it practical or theoretical?

Fiction vs. Non-Fiction Books

The idea here should be obvious. If you’re reading for entertainment, then go wild. Read whatever you want. But if you’re reading to learn about politics or science or history, it’s important to understand whether you’re reading something true or something made up.

That’s not to say that fiction doesn’t have its place in teaching us about politics or science or history, but we shouldn’t take what we read in a fictional book as fact.

Practical vs. Theoretical Books

The key difference between “practical” and “theoretical,” in this sense, is summed up well in this quote:

Theoretical books teach you that something is the case. Practical books teach you how to do something you want to do or think you should do.

For example, How to Read a Book is a practical book. It tells you how to intelligently read a book and gives you many actions you can take to do so. On the other hand, The Origin of Species by Charles Darwin is theoretical. It lays out Darwin’s ideas about evolution and tells us what evolution is, but doesn’t tell us how to do evolution.


I struggled with the importance of this chapter because there are really two ideas:

I agree with the former wholeheartedly, but I think for a different reason than the author does.

I’m afraid I have to disagree with the latter. Sure, you should know whether you’re reading fiction or non-fiction, but that’s obvious. And while I find the distinction between practical and theoretical books useful, I think it’s far less important than the author makes it out to be.

What’s more important to me is that I have a list of questions that I want answers to and determine whether the book will answer those questions. If the book answers my questions, then I don’t care what kind of book it is.

I also believe that good questions will replace Adler’s classifications. A question like “Who was the 44th president of the United States?” can only be answered by a theoretical, non-fiction book. I’m using the “theoretical” and “non-fiction” descriptions for consistency, but this works along any dimension.

That’s why I agree that it’s important to know what kind of book you’re reading. Specifically, you must know whether the book is the type of book that can answer your questions.


This chapter’s takeaway is a simple one: knowing what kind of book you’re reading and whether the book has answers to your questions is critical.

A question I had before starting to read How to Read a Book was, “How can I read books more effectively?”. Skimming through the book told me that Adler had many suggestions on how to do that, so I knew there’s a good chance the book would answer my question.

Personally, I don’t think classifying books is worthwhile. The only thing that matters is that my questions are answered.

I’m interested in hearing other opinions on this. Do you disagree with my takeaways? Am I just being pedantic? Hit me up on Twitter, and let’s talk.

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