One of the best philosophers working in Canada today is Margaret Somerville. She has devoted a lot of her energies to examining the ethics of assisted human reproduction and as a natural extension of this has been examining the issue of same-sex marriage, which she opposes.

Why does it make sense to extend your ethical framework from assisted human reproduction to same-sex marriage? The reason is that both attack the central importance to children of the natural ties and of motherhood and fatherhood.

She has written this very lucid article on the topic of same-sex marriage for The Australian. The Australian parliament recently resoundingly defeated same-sex marriage in a free vote.

Somerville makes the same general argument against same-sex marriage that the Iona Institute among many others make, namely that man/woman marriage is primarily about children and their need for a mother and father, rather than about adults.

But she deals very ably with some of the standard counter-objections to the traditional marriage position, for example, that some married couples can’t have children, or that being opposed to same-sex marriage is like being opposed to interracial marriage.

Somerville supports civil partnerships and believes unjust discrimination against gay people must come to an end, but not at the price of redefining marriage because to do undermines the right of a child to be raised by their own mother and father, where possible and desirable, a right the institution of marriage is primarily designed to uphold.

Mary McAleese has just come out in favour of same-sex marriage. She should study Somerville’s argument and then make clear whether she (McAleese) believes children ought ideally to be raised by their own biological parents, and if so, how society should give this relationship special protection if marriage is suddenly redefined in the way she wishes so that it no longer promotes the bond of mother/father/child?