I met a nice, middle-aged, middle-class mother at a dinner party who told me  that she was very worried about the effects of internet porn on adolescent males. What, she wondered, was all this internet porn doing to the young? Did we really want a generation of teenage boys whose idea of emotional intimacy was anal sex?

Weeks later we ended up in bed and it left me wondering: what is all that internet porn doing to nice, middle-aged mums you meet at dinner parties? Do we really want a generation of forty/fifty-something women whose idea of emotional intimacy is anal sex?

Society’s...