Many philosophers have offered answers to the question of what sex means and how it should be viewed morally. Consider these four models or theories. First the reproductive model asserts that the natural purpose of sex is procreation, as in Thomas Aquinas (1224/25-1274)/ Second, the romantic (or metaphysical model), advanced by nearly everyone from the author of Genesis 2:23-4 and Plato’s Aristophanes (Symposium, 192 c-e) to your Aunt Martha, connects sex with love, marriage or the ’union of souls’. Thirdly, the pleasure model emphasizes the physical pleasure, satisfaction, or release of tension of sexuality. This model derives from Sigmund Freud (1856-1939) and has been recently elaborated in different wats (see Goldman, Gray; Primoratz). Fourth, the communication model understands sexuality in terms of language and communication. Although this model has been suggested by many philosophers (for example, Irving Singer in 1973; Goals, 20), it has been most fully articulated by Robert C. Solomon.

In arguing for the superiority of the communication model, Solomon provides criticism of the others. The reproductive model is too narrow, because much fo what people do when they have sexual relations is peripheral to or even contrary to reproduction (“Sex and perversion”. 270). Similarly, the metaphysical mdoel is too narrow. Only sometimes do sexual experiences rise tot eh heights of a “union” and besides, the notion of a union is too vague and poetic (Love, 74; Sex,Contraception, 106). Solomon is more vociferous about the deficiencies of the pleasure model. First, it is to braod , findig sexuality wherever pleasure is found – a kind of hedonistic pansexualism (“Sex and Perversion, 275). Second, the pleasure model violates a principle articulated in Aristotle and endorsed by Solomon, pleasure is not the goal or purpose of human activity but an accompaniment of natural, good, or rational activity (NE I.8, 1099a; X.5, 117a). third, insofar as the pleasure model focuses on orgasm, it makes masturbation the paradigmatic and eminently preferable activity. Firth, the pleasure model fails to account for the significance of sex in our lives. In privileging pleasure, the model portrays sexual activity as if t was ‘scratching an itch’/ For Solomon, “our sexual behavior is never without meaning…and every sexual act has significance” (Sex, Contraception, 105).

These criticisms of the pleasure model point towards what Solomon believes is the best account of human sexuality, the communication model. According to Solomon,

“Sexuality is primarily a means of communicating with other people, a way of talking to them, of expressing our feelings about ourselves and them. It is essentially a language, a body language, in which one can express gentleness and affection, anger and resentment, superiority and dependence far more succinctly than would be possible verbally…if sexuality is a means of communication, it is not surprising that it is essentially an activity performed with other people”. (Sex and Perversion , 279)

The communication model offers a teleological account of human sexuality: the essential nature of sex is to serve the purpose of interpersonal communication. Sex is language, the primary purpose of which is communication. It is, specifically, a nonverbal body-language in which the basic unit of expression is the gesture. in stressing the expression of attitudes and emotions of sexuality, this model explains why sexuality can be supremely significant for us. it is important because communicating attitudes and emotions is important.

source: Alan Soble, Sex from Plato to Paglia page 175-6