“The most urgent problems we face with sex seldom have anything to do with technique. Kama Sutra, India, late eighteenth century.”

“Rather, we worry about how problematic sex has become with our long-term partner due to mutual resentments over childcare and finances; or about our addiction to internet pornography; or about the fact that we seem to crave sex only with people we don’t love; or about whether, by having had an affair with someone at work, we have irretrievably broken our spouse’s heart and trust.”

“Erections and lubrication simply cannot be effected by willpower and are therefore particularly true and honest indices of interest. In a world in which fake enthusiasms are rife, in which it is often hard to tell whether people really like us or whether they are being kind to us merely out of a sense of duty, the wet vagina and the stiff penis function as unambiguous agents of sincerity.”

“In the presence of someone who seems utterly assured of our virtuousness, we dare to share aspects of ourselves that we are otherwise frightened and ashamed of. We use words and gestures that would cause us to be labelled as maniacs in the world beyond. It can be a sign of love to be allowed to slap someone hard across the face or to clasp our hands forcefully around another’s neck. Our partners thereby demonstrate to us that they know we are essentially honourable. It doesn’t matter to them that we have darker sides; they can – like the ideal parent – see us whole and recognize us as being fundamentally good. We are granted an extraordinary opportunity to feel comfortable in our own skin when a willing and generous lover invites us to say or do the very worst things we can imagine.”

“When we are on the receiving end of this type of violence and rudeness, we may find a parallel pleasure, and a certain sense of strength, in being able to decide for ourselves just how insulted, hurt and dominated we are going to feel… We work through a fear of our fragility by being slapped and insulted at our command, enjoying the impression of resilience and empowerment afforded by encountering the worst that someone can think of inflicting on us – and surviving.”

“The orgasm itself marks the supreme moment when our loneliness and alienation are momentarily overcome.”

“Worringer argued that we all grow up with something missing inside us. Our parents and our environment fail us in distinctive ways, and our characters hence take shape with certain areas of vulnerability and imbalance in them. And crucially, these deficits and flaws determine what is going to appeal to us and repel us in art.”

“The solution to long-term sexual stagnation is to learn to see our lover as if we had never laid eyes on him or her before.”

“In a perfect world, all couples would be visited by a psychotherapist on a weekly basis, without even having to put themselves forward for the service. The session would simply be a regular feature of a good, ordinary life, as the Friday-evening meal is for Jews, and would offer some of the same cathartic function as this ritual. Above all, neither party would be made to feel by society that he or she was crazy for having therapy – which is currently the main reason people neglect to see therapists and therefore slowly go crazy.”

“Pornography, like alcohol and drugs, undermines our ability to endure certain kinds of suffering which we have to experience if we are to direct our lives properly. More specifically, it reduces our capacity to tolerate our ambiguous moods of free-floating worry and boredom.”

“The boldness displayed by middle-aged married men when they are trying to seduce other women should never be confused with confidence: it is just the fear of death, which breeds an awareness of just how infrequently they are ever going to have the opportunity to sample such moments again.”