(1.) See St. Thomas Aquinas, Summa Contra Gentiles, trans. by V. J. Bourke (Notre Dame: Notre Dame University Press, 1975), bk. III, pt. II, ch. 122, pp. 142-147; The Summa Theologica, trans. by fathers of the English Dominican Province (London: Burns Oates & Washbourne, s.a.), vol. 13, pt. II/ii, q. 154, art. 1, 11-12, pp. 130-133, 157-161.

(2.) S. Ruddick, "Better Sex," in R. Baker and F. Elliston (eds.), Philosophy and Sex (Buffalo: Prometheus Books, 1975), p. 91.

(3.) Ibid., p. 92.

(4.) Ibid, p. 91.

(5.) Ibid., p. 95.

(6.) R. Scruton, Sexual Desire: A Philosophical Investigation (London: Weidenfeld & Nicolson, 1986), p. 289.

(7.) Ibid., p. 292.

(8.) Ibid., p. 294.

(9.) See A. Ellis, "Casual Sex," International Journal of Moral and Social Studies, vol. 1 (1986); I. Primoratz, "What's Wrong with Prostitution?", Philosophy, vol. 68 (1993).

Thomas Nagel's account in "Sexual Perversion," The Journal of Philosophy, vol. 66 (1969), fails for the same reason: what it presents as perverted sex is merely non-ideal sex. To be sure, Nagel's ideal differs from that of Scruton's, both in contents and, more importantly, in the type of evaluation involved. On Nagel's account, sex that combines embodiment and reflexive multileveled mutual recognition of arousal by arousal is not a moral, but a morally neutral, purely sexual ideal.

(10.) R. Solomon, "Sex and Perversion," in R. Baker and F. Elliston (eds.), op. cit., p. 282.

(11.) R. Solomon, "Sexual Paradigms," The Journal of Philosophy, vol. 71 (1974), p. 345.

(12.) R. Solomon, "Sex and Perversion," pp. 284-285.

(13.) A. Goldman, "Plain Sex," Philosophy and Public Affairs, vol. 6 (1976/7), p. 285.

(14.) Ibid., p. 286.

(15.) S. A. Ketchum, "The Good, the Bad and the Perverted: Sexual Paradigms Revisited," in A. Soble (ed.), Philosophy of Sex (Totowa: Littlefield, Adams & Co., 1980), p. 149.

(16.) Ibid., p. 152.

(17.) Ibid., p. 153.

(18.) D. Levy, "Perversion and the Unnatural as Moral Categories," in A. Soble (ed.), op. cit., p. 179.

(19.) Ibid., p. 186 n. 43.

(20.) See ibid., pp. 185-186, n. 42.

(21.) For an interesting attempt to display the sources of these inconsistencies and confusions, see James M. Humber, "Sexual Perversion and Human Nature," Philosophy Research Archives, vol. 13 (1987/8).

(22.) Marquis de Sade, The Complete Justine, Philosophy in the Bedroom, and Other Writings, ed. and trans. by R. Seaver and A. Wainhouse (New York: Grove Press, 1965), pp. 320, 323.

(23.) See ibid., pp. 314-329.

For another version of the view that sexual perversion is essentially sexual behavior markedly deviating from the prevailing sexual taste, see Joseph Margolis, "Perversion," Negativities: The Limits of Life (Columbus: Charles E. Merrill, 1975). Margolis argues that "what is most intimately involved in sexual desire eludes every form of moral review, being not voluntary, and what is subject to review is often made such because of independent considerations, as in the cruelty of sadists or in the invasion of privacy by voyeurs. So the restriction of sexual practices reflects the variable tastes of one society or another" (p. 121). The proper attitude to sexual perversion, thus understood, is tolerance (p. 128).

(24.) M. Slote, "Inapplicable Concepts and Sexual Perversion," in R. Baker and F. Elliston (eds.), OP. Cit., p. 263.

(25.) By discarding the idea of sexual perversion, philosophers would only do what American psychiatrists have already done. Up to 1987, the Diagnostic and Statistical Manual of Mental Disorders issued by the American Psychiatric Association treated all traditional sexual perversions except homosexuality as mental disorders. To be sure, the old term "sexual deviations" had by then been replaced by the less loaded "paraphilias," but they were described in the following way: "The Paraphilias are characterized by arousal in response to sexual objects that are not part of normative arousal-activity patterns and that in varying degrees may interfere with the capacity for reciprocal, affectionate sexual activity" (Diagnostic and Statistical Manual of Mental Disorders, 3rd ed., revised [Washington: American Psychiatric Association, 1987], p. 279). This understanding of paraphilias was at odds with the definition of mental disorders in the same manual which expressly ruled out mere deviance from social norms as ground for diagnosing mental disorder, and required the suffering or increased risk of suffering some harm by the agent for such a diagnosis (ibid., p. xxii). And it showed that the core idea was still that of deviation from some norm of conventional morality or prevailing sexual taste. Frederick Suppe was therefore right in saying that the inclusion of the traditional sexual perversions, under the new name of paraphilias, in the mental disorders manual "is unwarranted, unscientific, and only serves to reinforce the suspicion that in the psychosexual arena, at least, psychiatry reduces to the codification of social mores masquerading as objective science" (F. Suppe, "The Diagnostic and Statistical Manual of the American Psychiatric Association: Classifying Sexual Disorders," in E. A. Shelp (ed.), Sexuality and Medicine [Dordrecht: D. Reidel, 1987], vol. 2, p. 132). However, the current position of the American Psychiatric Association is significantly different: paraphilias are now said to be "characterized by recurrent, intense sexual urges, fantasies, or behaviors that involve unusual objects, activities, or situations and cause clinically significant distress or impairment in social, occupational, or other important areas of functioning" (Diagnostic and Statistical Manual of Mental Disorders, 4th ed. [Washington: American Psychiatric Association, 1994], p. 493). That means that mere deviance from social norms is no longer enough and that a sexual inclination or behavior will be treated as paraphiliac only if it brings about distress or impairment of some important function in the agent. If it does not, an unusual sexual inclination or behavior will be considered just that, and nothing more.

(26.) This paper was read at philosophy departments of the Australian National University, Monash University, and University of Melbourne, October-December 1996. I am grateful for helpful comments I received on these occasions. I have also benefited from comments by an anonymous referee for this journal.