We owe a lot to the sex lives of Greeks. Ancient Greece gave us the origins of the names and concepts for homosexuality, homophobia and nymphomania, as well as narcissism and pederasty. The Romans talked freely to each other in toilets and were equally community-minded when it came to sex, with a reputation for lasciviousness and orgies. Georgians, we believe, were smutty, and Victorians were prudes and hypocrites. (All of these are partial truths.) We like to use sex as a mirror of an era, and to make judgments accordingly. What then, are we to make of us right now?

This is the most sex-positive age ever, right? We are liberal and comfortable with sex like no other people have ever been. Our magazines publish articles on how to get on better with your clitoris. Porn is freely available (and accessed by teenagers). Erotic books are bestsellers, however badly written. TV broadcasts shows in which the contestants are naked, or have sex in a box, or make a sex tape on camera. If sexual choice were a shop, it would be a hypermarket, with dizzyingly long aisles of every possibility: straight, gay, bi, trans, poly, fluid, each with its own culture and each widely accepted.