Once upon a time, this idea of having a trained, disciplined, cultivated memory was not nearly so alien as it would seem to us to be today.

Monotony collapses time. Novelty unfolds it.

Evolution has programmed our brains to find two things particularly interesting, and therefore memorable: jokes and sex - and especially, it seems, jokes about sex.

Growing up in the days when you still had to punch buttons to make a telephone call, I could recall the numbers of all my close friends and family. Today, I'm not sure if I know more than four phone numbers by heart. And that's probably more than most.

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.

If you want to live a memorable life, you have to be the kind of person who remembers to remember.

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.