By expanding our awareness of unknown unknowns, an antilibrary may even be an antidote to the Dunning–Kruger effect, where we tend to overestimate the extent of our knowledge. Whether in a private or a public library, being surrounded by books we haven’t read yet—in the case of Umberto Eco, too many books to read in a lifetime—is a humbling experience.

The goal of an antilibrary is not to collect books you have read so you can proudly display them on your shelf; instead, it is to curate a highly personal collection of resources around themes you are curious about. Instead of a celebration of everything you know, an antilibrary is an ode to everything you want to explore.

When an author mentions another book, check the exact reference and make a note of it. By doing so, you will have a list of all the relevant sources for a book when you are done reading it. Then, research this constellation of books. It is unlikely all the sources on the list will seem interesting to you. Sometimes, only a short passage of the source was relevant to the book you just read. But other times, you will discover a book that genuinely piques your curiosity.

If you read a book that you particularly enjoyed and would like to learn more about the topic, simply ask people if they know of any similar books. If you don’t have many readers in your circles, you can use Goodreads or Amazon to find similar books. Read the reviews to decide whether they would be a good addition to your antilibrary.

I have read quite a few interesting books that I randomly bought in a bookstore because the cover looked nice and the title was intriguing. While looking for sources and similar books are both effective ways to build an antilibrary, make sure you leave space for chance discoveries.

While there is no perfect proportion, the more you read, the more you will expand your perimeter of knowledge, and the more unread books will be added to your antilibrary. It is not a bad thing, it means you are progressively turning unknown unknowns into known unknowns.

At first, building an antilibrary can feel strange and even a bit anxiety-inducing. So many books—am I ever going to be able to read them all? Isn’t that a waste of money? Remember that knowledge is a process, not a possession. In addition, building an antilibrary is an investment in yourself which should stay within your means. Even if you only have 3-5 books you haven’t read on your shelf, this is already a great step in expanding your intellectual horizon.