First, Kang is correct to point out that there is nothing bad about sex as such. The Anscombe Society does not regard sex as categorically good or categorically bad. Whether sex is inherently good – as it often is – depends on a number of factors: whether the persons involved are permanently and exclusively committed to each other, whether the act is a free expression of their commitment, etc. In this respect, it’s true, sex between unrelated adults is decidedly unlike incest or adult-youth relations, which McGinley and the Anscombe Society consider inherently wrong. Our moral intuitions, in this case “repugnance”, may not be an argument per se about what we should believe in the case of incest and adult-youth relations. But, our moral theory (in this case, our theory of sexual ethics) should accommodate most of our intuitions about what is right and wrong, just as a plausible theory about the world should accommodate our observation of it.
Secondly, Kang takes issue with the claim that instrumentalization of the body always occurs outside of a marital context. And if it always occurs outside of marriage, why isn’t sex within marriage instrumentalizing the body as well? Kang suggests that Anscombe’s position requires an understanding of sex within marriage as permissible, no matter what. But that is not our view. One could imagine spouses who are deceitful or unfaithful to their commitment but nevertheless continue to have sex – they, too, would be instrumentalizing each other. Rather, we think that sex is good when and only when it is the consummation of a full union of persons on many levels: the bodily bond that completes a couple’s total commitment to each other at the level of their wills. So for sex to constitute full marital commitment, it is necessary but insufficient that it take place within marriage. Full marital commitment requires the unity of persons not just bodily, but also emotionally, mentally, etc.
Kang also suggests that the idea that there are moral constraints on what people should use sex to express – or, relatedly, on the proper purpose of sex – is a distinctively theological view. It is not. It is, rather, an ordinary moral belief that almost everyone reading this already accepts, even if we disagree about what those constraints are. For instance, most of us believe that sex must be a free expression – and not just in the same way that we think most activities should be free: nonconsensual sex strikes us as a far greater violation than, say, being forced to eat vegetables or play an instrument. People also generally agree that sex should not be used as an expression of filial love (even with an adult son or daughter capable of consenting) or fraternal love (even where children with complications will not arise, as for example between two brothers or sterile siblings). And many agree that sex should not be used to express passing acquaintanceship or only for one’s own gratification – unlike, say, tennis. Given this framework, the claim that sex should express a permanent and exclusive commitment is not radically different in kind. Almost everyone recognizes such limits.
What gives rise to our notion of these limits? We argue that sex calls for a commitment that is both permanent and exclusive as it is oriented towards bearing and rearing children— a commitment indefinitely into the future to both any kids that may arise and to both parties involved. Now, it falls to Kang to defend the above limits that we intuitively accept on the proper use of sex that stops short of the limits that the Anscombe Society accepts.