Summary of "How to Mark a Book" by Mortimer Adler

by Thomas Colbyry

What is the best way to get the most out of a book? In his essay "How to Mark a Book," American philosopher Mortimer J. Adler extolls the virtues of not only reading, but writing "between the lines." The man who wrote the primer on liberal education, "How to Read a Book," suggests that annotating books as you read makes for "the most efficient kind of reading." Adler distinguishes between three kinds of readers: those who own books and do not read them; those who own books and read them occasionally and those who own books, read them and mark them up.

Step 1

Underline or highlight sentences that catch your attention using a pencil. If you have previously underlined a sentence and want to emphasize it further, near it draw vertical lines in your margins.

Step 2

Place stars, asterisks or other markings of your choice in the margin near what you consider the 10 or 20 most important points in the book and fold the bottom corner of the pages where you have made these markings. This will allow you to remove your book from the shelf and locate everything of importance in it quickly.

Step 3

Place numbers in the margin to trace the steps of an argument the author is making.

Step 4

Use numbers in the margin also to string together threads of an author's point throughout the text. For instance, if an author discusses the role of salt in the Roman economy on page 12, put a "3" here and on each subsequent page the author discusses the issue. In a blank page in the back of the book, write "Role of salt: 3" and the pages upon which "3" appears.

Step 5

Locate important words or phrases, such as the word "persuasion" in Jane Austen's novel of the same name, and highlight or circle them each time they appear. This allows you to see not only an author's use of repetition but also her variations on a given word or theme.

Step 6

Write important questions that you would like to ask the author, or answers to questions the author poses, in the margins and create a subject index of these questions and answers in the blank pages at the end of the book.

Tips & Warnings

  • To follow Adler's guidelines in "How to Mark a Book," you need to own a copy of the book you will be marking. As he mentions, "You shouldn't mark up a book which isn't yours."


  • "How to Read a Book"; Mortimer J. Adler and Charles Van Doren; 1972
  • "The Pleasures of Reading in an Age of Distraction"; Alan Jacobs; 2011

About the Author

Thomas Colbyry is a writer living in Marquette, Mich. Currently pursuing a B.A. in English, he works as a writing tutor and contributes book reviews to several publications. Colbyry often covers topics related to literature, specializing in early modern, Restoration, 18th-century and Victorian British literature, as well as the literature of Japan.

Photo Credits

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