This is a point often made in the current debate about same sex marriage – generally with an air of aphoristic finality, as if declaiming a truism that only an utter fool (or bigot) could deny. The emphasis on marriage’s link with procreation, it is implied (or, often, stated explicitly), is thus a post hoc rationalisation cobbled together by those who wish to exclude same-sex couples arbitrarily from an institution that is really just about two people loving one another and seeking mutual happiness.
The first point I’d make in response to that argument is that you could easily rephrase it as:
How can you say that marriage is about two people loving one another and seeking mutual happiness, when plenty of married couples are miserably unhappy and unloving?
In other words, the outcome of particular marriages shouldn’t be confused with the purposes of marriage – and of the state’s recognition and regulation of marriage.
The second (and more substantial) point is well expressed by David Novak in an essay on the ABC Religion & Ethics site. Novak quotes Prof Martha Nussbaum, a supporter of same-sex marriage, who writes that:
marriage … supports several distinct aspects of human life: sexual relations, friendship and companionship, love, conversation, procreation and child rearing, and mutual responsibility.
Novak divides these purposes into two categories. The first is what Prof Nussbaum calls the “expressive”, and Novak calls the “private”, purposes of marriage: “sexual relations, friendship and companionship, love, conversation, … and mutual responsibility”. The second is “procreation and child rearing”, which Novak argues is the only aspect of marriage in which the state has any valid interest. After all (as supporters of cohabitation outside marriage have been telling us for decades), why should it be any concern of the state with whom, and how, I engage in “sexual relations, friendship and companionship, love, conversation, … and mutual responsibility”? However, the state, and society as a whole, does have more of an interest in the procreation and rearing of children.
Novak then goes on to address the objection quoted at the start of this post:
But, if marriage’s sole public reason is procreation, and coincidentally being responsible for those whom a couple has procreated, then why has marriage never been “limited … to the fertile, or even to those of an age to be fertile,” as Nussbaum puts it?
I would answer that objection by citing the old legal principle: de minimis non curat lex, which could be translated loosely as “the law is only made for what usually obtains.”
The fact is, the majority of people who marry are fertile and are of an age to be fertile. And how could we reasonably establish a criterion to determine who is fertile and who is not? Moreover, in an age when new reproductive technologies are enabling persons heretofore assumed to be sterile to become parents, almost no one can be presumed to be incurably infertile.
Even if a couple does decide between themselves from the outset not to have children, that is their private agreement which in no way impinges upon the public reason for marriage per se.
The question is whether the inherently non-procreative nature of same-sex relationships makes “marriage” an inappropriate word for them, given their capacity for “sexual relations, friendship and companionship, love, conversation, … mutual responsibility” and, yes, the raising of children. In other words, is “marriage” the word we use for “a loving relationship, recognised and endorsed by the state, between two consenting adults”, or is it the word we use specifically for “the union with procreative potential”, pre-dating both church and state, and the exclusive property of neither?
Now, that’s something that it’s possible to have a debate about. But what’s not possible (though some people are trying very hard to make it so) is to say that the existence of childless married couples makes the linking of marriage and procreation a self-evident absurdity.