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.

When you want to get good at something, how you spend your time practicing is far more important than the amount of time you spend.

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

Truman Capote famously claimed to have nearly absolute recall of dialogue and used his prodigious memory as an excuse never to take notes or use a tape recorder, but I suspect his memory claims were just a useful cover to invent dialogue whole cloth.

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.

Once I'd reached the point where I could squirrel away more than 30 digits a minute in memory palaces, I still only sporadically used the techniques to memorize the phone numbers of people I actually wanted to call. I found it was just too simple to punch them into my cell phone.

A meaningful relationship between two people cannot sustain itself only in the present tense.