Most people would agree that bestiality—by which, I mean a sex act that a human being performs upon an animal—is morally wrong, but scarcely can a person explain why. Most people simply assume that bestiality is wrong while having no reason for that. It is important, then, to establish a reason as to why or why not bestiality is morally permissible because Reason is needed for authentic living. Reason is how human beings access Truth; that is the basis for Virtue and hence authentic living. As such, the modern imagination finds itself in a paradox. The liberal social order has an ethical theory of sex, but its theory can’t explain why bestiality is morally impermissible. The question, then, is whether (1) the liberal ethical theory of sex is wrong or (2) bestiality is morally permissible.
The liberal ethical theory of sex is implicitly Christian, albeit secular, in its praxis. Like Christians, liberals deify “love” as self-evidentially good. Sex is thought of as a part or expression of love. Since liberals are materialists, love is not metaphysical, but they only perceive love in terms of preferences or pleasure. The liberal ethical theory of sex considers only consensual sex to be morally permissible sex. Accordingly, bestiality must also be morally permissible. In such an act, the only actor whose will (i.e., consent) is relevant is that of the human being. As a society, we kill animals to eat them, so we do not care about the consent of animals; the will of the animal, then, is not relevant. As such, bestiality must be morally permissible, but it is not as Reason vis-à-vis our basic human instincts tell us—so the liberal ethical theory of sex must be wrong.
Its error starts with the assumption that the purpose of sex is pleasure. The arbiter of permissible versus impermissible sex, then, falls to consent. And yet, there are species of animals that do not experience pleasure during sex. Moreover, sex is an evolutionary mechanism to promote fertile breeding and hence the survival of the species. Evolution itself precedes consciousness; evolution even takes place in non-conscious beings. And consciousness precedes consent. Thus, the purpose of sex can’t be pleasure, and the arbiter of permissible sex can’t be consent.
But, contrarily, the purpose of sex is determined by its nature as an evolutionary mechanism. The purpose of sex is to promote fertile breeding and eventual biological improvement. Since genetic improvement can lead to moral improvement, permissible is sex that can serve that evolutionary purpose, such as coitus. And, further, coitus between persons of high genetic stock should be highly encouraged. But sex that can’t lead to procreation whatsoever, never mind evolutionary progress, is impermissible.