the first sexual revolution can be traced in some of the greatest works of literature, art and philosophy ever produced – the novels of Henry Fielding and Jane Austen, the pictures of Reynolds and Hogarth, the writings of Adam Smith, David Hume and John Stuart Mill. And it was played out in the lives of tens of thousands of ordinary men and women, otherwise unnoticed by history, whose trials and punishments for illicit sex are preserved in unpublished judicial records. Most startling of all were my discoveries of private writings, such as the diary of the randy Dutch embassy clerk Lodewijk van der Saan, posted to London in the 1690s; the emotional letters sent to newspapers by countless hopeful and disappointed lovers; and the piles of manuscripts about sexual freedom composed by the great philosopher Jeremy Bentham but left unpublished, to this day, by his literary executors. Once noticed, the effects of this revolution in attitudes and behaviour can be seen everywhere when looking at the 18th, 19th and 20th centuries. It was one of the key shifts from the pre-modern to the modern world.