What makes things memorable is that they are meaningful, significant, colorful.

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.

Memory training is not just for the sake of performing party tricks; it's about nurturing something profoundly and essentially human.

All across Africa, the Pacific and the Americas, we find cultures that didn't know about mouth kissing until their first contact with European explorers. And the attraction was not always immediately apparent. Most considered the act of exchanging saliva revolting.

The art and science of memory is about developing the capacity to quickly create images that link disparate ideas. Creativity is the ability to form similar connections between disparate images and to create something new and hurl it into the future so it becomes a poem, or a building, or a dance, or a novel. Creativity is, in a sense, future memory.

Over the last few millennia we've invented a series of technologies - from the alphabet to the scroll to the codex, the printing press, photography, the computer, the smartphone - that have made it progressively easier and easier for us to externalize our memories, for us to essentially outsource this fundamental human capacity.

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.