Experts step outside their comfort zone and study themselves failing.

What distinguishes a great mnemonist, I learned, is the ability to create lavish images on the fly, to paint in the mind a scene so unlike any other it cannot be forgotten. And to do it quickly. Many competitive mnemonists argue that their skills are less a feat of memory than of creativity.

It is forgetting, not remembering, that is the essence of what makes us human. To make sense of the world, we must filter it. "To think," Borges writes, "is to forget.

The fact that books today are mostly a string of words makes it easier to forget the text. With the impact of the iPad and the future of the book being up for re-imagination, I wonder whether we'll rediscover the importance of making texts richer visually.

Some memorizers arbitrarily associate each playing card with a familiar person or object, so that the king of clubs is represented by, say, Tony Danza. The grand masters associate each card with a person, an action, or an object so that every group of three cards can be converted into a sentence.

Invented languages have often been created in tandem with entire invented universes, and most conlangers come to their craft by way of fantasy and science fiction.

Jonah Lehrer is one of the most talented explainers of science that we’ve got. What a pleasure it is to follow his investigation of creativity and its sources. Imagine is his best book yet.