Sadomasochism:subsumes a whole array of practices whose practitioners may have very little in common. Sexologists have commonly included under this heading everything from love bites to lust-murder. What, if anything, conceptually unites the desire to receive mild pain, to give mild pain (and even these desires may take diverse forms), to be tied up or to bind one's partner, to participate in scenarios of humiliation or domination, or to receive severe pain or to inflict it? Perhaps the common factor in all these phenomena is some form of suffering, from the minor to the extreme, which has been given an erotic meaning by the actors involved. Whether, however, all forms of suffering have the same eroticized meaning is open to question.
The sadomasochistic practice with possibly the longest history of recognition as a sexual perversion, even before the development of the concept, must be flagellation. There have been numerous historical studies of corporal punishment, though it may be queried how far these illuminate one of the murkier areas of sexual diversity, or are merely a specialized form of pornography masquerading as ‘science’. Flagellation was long known to arouse sexual desire by stimulating nerves in regions adjacent to the genitals. It was employed, for example, in brothels, as a means of arousing the sluggish desires of the impotent or elderly. Sexual arousal tends to raise the threshold at which pain is experienced, and thus love bites, pinches, slaps, and other non-specifically arousing acts may feed back into the process of sexual arousal and enhance its intensity.