In other words, as far as technologies go, the book endures for very good reason. Books work.

The goal is not to read as many books as possible. The goal is to gain as much wisdom as you can.

Using models while reading can also help you get more out of the book. Here are some examples of paths they might lead you down: Confirmation bias: Which parts of this book am I ignoring? Does this book confirm my opinions? (Okay, but does it actually affirm your beliefs or are you just seeing what you want to see? If you cannot think of a single point in the book that you disagreed with, confirmation bias is likely distorting your reasoning.) Bayesian updating: What opinions should I change in light of this book? How can I update my worldview using the information in it? Keep in mind the words of John Maynard Keynes: “When the facts change, I change my mind. What do you do, sir?” Incentives: What motivates the characters or the author? What are they seeking? What is their purpose? Here’s how Kurt Vonnegut described the importance of incentives in books: “When I used to teach creative writing, I would tell the students to make their characters want something right away—even if it’s only a glass of water. Characters paralyzed by the meaninglessness of modern life still have to drink water from time to time.” Availability bias: Are the books I have recently read affecting how I perceive this one? How are my immediate past experiences shaping my reading? Am I assigning undue importance to parts of this book because they are salient and memorable? Social proof: How is social proof—the number of copies sold, bestseller status, the opinions of others—affecting my perception of this book? Is the author using social proof to manipulate readers? It is not unusual for authors to buy their way onto bestseller lists, providing social proof that then leads to substantial sales. As a result, mediocre books can end up becoming popular. It’s a classic case of the emperor having no clothes, which smart readers know to look out for. Survivorship bias: Is this (nonfiction) book a representation of reality or is the author failing to account for base rates? Survivorship bias is abundant in business, self-help, and biographical books. A particular case of a successful individual or business might be held as the rule, rather than the exception. Utility: If a book offers advice, does it have practical applications? At what point do diminishing returns set in?

Author and librarian Nancy Pearl advocates the “Rule of 50.” This entails reading the first 50 pages of a book and then deciding if it is worth finishing. The Rule of 50 has an interesting feature: once you are over the age of 50, subtract your age from 100 and read that many pages. Pearl writes: “And if, at the bottom of Page 50, all you are really interested in is who marries whom, or who the murderer is, then turn to the last page and find out. If it’s not on the last page, turn to the penultimate page, or the antepenultimate page, or however far back you have to go to discover what you want to know.…When you are 51 years of age or older, subtract your age from 100, and the resulting number (which, of course, gets smaller every year) is the number of pages you should read before you can guiltlessly give up on a book.…When you turn 100, you are authorized (by the Rule of 50) to judge a book by its cover.”

Most of us were taught as children to treat books as something sacred—no folding the page corners, and no writing in the margins, ever.

Book summary services miss the point. A lot of companies charge ridiculous prices for access to vague summaries bearing only the faintest resemblance to anything in the book. Summaries can be a useful jumping-off point to explore your curiosity, but you cannot learn from them the way you can from the original text.*

The most common and sensible location for putting down thoughts, critique or notes was the margin of the medieval book. Consider this: you wouldn’t think so looking at a medieval page, but on average only half of it was filled with the actual text. A shocking fifty to sixty percent was designed to be margin. As inefficient as this may seem, the space came in handy for the reader. As the Middle Ages progressed it became more and more common to resort to the margin for note-taking.

Dots and lines are particularly common ingredients of such footnote symbols. Interestingly, their first appearance is not as a connector of comment and text, but as an insertion mark that added an omitted line into the text.

Evidently, these two groups of bookmarks—static and dynamic—provided very different approaches to marking information—and thus to a book’s use. Readers who added clip-on or “spider” bookmarks anticipated they would need to retrieve information not from one single page but from a changing number of pages. In other words, movable bookmarks served an audience with a shifting knowledge “appetite,” while the static ones encouraged a more “ritual” use of a book. In other words, both types are telling, in their own way, about medieval reading culture.

Step 3: Set up reading storage and a reading environment.

Jesuit manuals such as Jeremias Drexel’s Aurifodina, subtitled The Mine of All Arts and Sciences, or the Habit of Excerpting, explained how to best take notes from reading to create commonplace books: personal notebooks of reading extracts that contained the religious, ethical, and political maxims deemed necessary to lead a good life. There were even admonitions about which texts not to read and how not to fold page corners or to mark texts with fingernail scratches.