Some of the great writers have made compact observations on sexual intercourse. Rabelais called it the "beast with two backs," Andrew Marvell called it "one ball," and Lord Chesterfield said that the "pleasure is momentary, the position ridiculous." Kant (whose very name elicits titters from high school wits, or nit-wits) reduced marriage to each partner's possession of the other's sexual organs.
That Venus or Cupid is the true ruler of the universe can be established by the fact that sexual innuendo is never far from the surface of almost all conversations, that we are deeply curious about others' sex lives (see the supermarket gossip tabloids), and, above all, by the fact that intensely ambitious politicians--Bill Clinton, John Edwards, Eliot Spitzer, Anthony Weiner, Shelly Silver, Senator Vitter, and former IMF head Strauss-Kahn, among many--have imperiled their careers, not for love (a la Governor Mark Sanford) but for casual sex. Careful (or prurient) readers of history, moreover, soon come to believe that just about everyone slept with everyone else. And when prudish censoriousness rears its ugly head, one may well, in a Nietzschean frame of mind, stipulate that there is no sexual morality that is not grounded in envy.
The norms of society require that a man marry a respectable woman and confine his respectful sexual activity to the marriage bed. In other words, a gentleman does not masturbate, cheat on his wife, use force on her, or visit a prostitute. But the curious thing about the last item is that when courting a woman--a process in which each, incidentally, dresses up with the potential aim of eventually undressing---the man pays for dinner, theater, and transportation, with the expectation that the woman, sooner or later, may grant him sexual favors; how does that differ from the frowned-upon prostitution? Nay, at the end of the dating process--marriage--the man provides money, shelter, jewels, and furs, while the woman provides sex (unless she has a headache or the monthlies), and the same question applies.
A curious fact that almost no one questions is that men in all times and places (at least until the advent of the Pill) pursue women. Why? Besides the shallow answers--that men are physically stronger, or the Woody Allen suggestion that men have millions of sperm cells and women have only one egg--there are three serious explanations. One is that men are more easily aroused than women, who normally need the lubricant of amorous attraction. In an affair in which each betrays the other, the woman may regret having yielded to a scoundrel, but the man will never regret the sex. Another answer is that in sex the woman's body is invaded, a humiliation arguably no different from the territoriality among animals and nations. (In antiquity, homosexuality was considered degrading only in the passive partner.) The man therefore must pay entrance fees in the form of saying something like, "I love you" and "You're beautiful."
But by far the most important reason is the existence of a womb. Often in the wake of an act of sexual intercourse, matters are finished for the man but may just be beginning for the woman. In other words, becoming pregnant can massively change a woman's life, even imperil it, but the man can glibly disappear into the woodwork. See The Scarlet Letter. The two sexes therefore bring vastly different psychologies to the bed. (The Pill somewhat leveled the playing field.) From this innate feminine sensitivity to the consequences of one's actions (a sensitivity lacking in almost all other forms of human behavior) came the venerable myth that while men are pigs, women are frigid; that women do not enjoy sex as much as men do. No! They clearly do, but they just have much more to worry about. Hence also the famous double standard.
Another curious thing about sex is that it is misunderstood. An octogenarian once advised young men to bed as many women as they could in order to feel contentment in old age. That assertion caps the argument that sex is mainly not about sensual pleasure--for what is left of such long-ago physical experience to an old man reminiscing? No, many forms of copulation have to do rather with vanity. After all, physical gratification can easily be had through masturbation or a prostitute, but thoughtful men find such avenues unfulfilling (though the argument, in the latter case, that it is shabby to pay for sex is negated by the fact that we pay for all other pleasures, including marriage). It is rather "scoring" that matters; that is, a man treasures the knowledge that a woman, especially many women--attractive and classy ones, to boot--willingly surrendered herself to his charms, that in the wake of self-protective reluctance due to the dangers of pregnancy, she decided that he was notably worthy to be allowed entry, he was good enough for her to run a risk. Going to a prostitute or the village nymphomaniac, by contrast, is playing tennis without a net. (In the words of John Donne [in another connection], "We see by this it was not sex.")
Women traditionally were, moreover, unready to yield, or at least to yield too soon, for fear that the man would then leave for good. If sexual pleasure were central, would not the man rather stay with a reliably giving woman than pursue other women who may turn out not be so open to him? What matters, then, is not the amount and intensity of sex but the number of women one has experienced it with, even only once. Men, in short, really seek the pride expressed in the self-consoling last words of a dying Shakespeare character who is the object of the amatory rivalry of two women: "Yet Edmund was beloved!" For "beloved," read "sexually magnetic."
Since the rise of feminism, moreover, it has been established that women--some? many?--also have (and secretly always had) an interest in variety and experimentation, in scoring. But because of the plumbing, as well as the possibility of unintended pregnancy and the certainty of the double standard in society, that all-important sense of serial conquests is necessarily greater in the man. In short, by highlighting a man's talent at overcoming women's circumspection, scoring is more akin to being a successful trial lawyer or a winning pitcher than to being a sybarite. It is not mainly about pleasure but about ego, vanity, narcissism.
Of course, if all this is too complicated, one can always choose celibacy and have sex exclusively on the brain, or in one's dreams, or with one hand--as Rush Limbaugh likes to put it in another connection--tied behind one's back.