Adam’s father recently passed away. So now he has a nice farm. But what he doesn’t have is a housekeeper, cook, charwoman, or womb. But his neighbour Steve has several daughters. Any one of them could fulfil all the functions Adam needs. A quick visit to Steve reveals which of his daughters he will make available for Adam’s attention.

Adam has a long-term lover, who is quite understanding of his new courtship with Steve’s daughter Nicola. He’s married himself and has several children by his wife.

This is traditional marriage — an arrangement between men to facilitate the transfer of property down the male line.

But the world has changed. Nowadays we need at least plausible deniability that things are still done this way.

And so marriage has changed. The “brand” has been detoxified. It has been repackaged as a loving partnership of equals entered into freely by both parties.

When people complain about gay marriage undermining “traditional marriage” they are getting it arse about face. Traditional marriage undermined itself long ago.

I used to think that other people’s marriages had nothing to do with my marriage. I would switch off my brain if ever I heard people complaining about what “gay” marriage would mean for their marriage.

But I think my impatience with the people making this argument blinded me to the fact that participation in a public social arrangement, such as marriage, is not an entirely individual activity. Marriage exists in a social context. As such, our society’s agreements about what a marriage is define it.

And that argument accepts that it DOES matter what kinds of marriages other people have. Would I have wanted to get married if I believed it was fundamentally about my husband owning me? If I lived in a cultural context where marriage was an expression of gender inequality? No, I would not. (Or perhaps I would have felt I had no choice in the matter.) And that is the case regardless of whether I personally chose to change my name (I did not) or wanted to be “given away” or (shudder) have my fiancé ask for my father’s permission to marry.

I could buy into marriage because the story of marriage that I had been told, and had witnessed in my family, was that it was an arrangement agreeable to both parties and characterised by love and respect.

I’ve been rereading The Republic recently. Plato was a lot of things, but a feminist was not one of them. I had forgotten the bits where he talked about relationships — about how the relationship you had with your wife was one characterised (and devalued) by its functionality. The sex you (a man) have with your wife is procreative. It’s not the pure kind of sex you have with your (male) lover, unsullied by any kind of practical necessity.

Platonic love is often misunderstood as non-sexual love between friends of the opposite gender. But it was really sexual love between friends of the same gender. That was the truly romantic love. The love you chose, the love that was both spiritual and physical. Not like the practical love you expressed with a woman you wanted to bear your children.

That’s something else that changed over the past half century or so — sex between men and women was opened up to the possibility of Platonic love. Improvements in contraceptive options were a part of that, as were changes in women’s status in society. Sex as a consensual and mutually agreeable activity between a man and a woman has become mainstream and celebrated in a way that has not always been the case.

So marriage and sexual relationships have both been changing pretty rapidly over the past 50-100 years. We can redefine marriage as being something that is about two people who are in love. But if we redefine it that way, then we don’t get to be surprised that people who are in love want to get married. Being in love is not something that has ever been exclusive to heterosexual relationships. If marriage is about love between two equals, then relationships based on romantic, sexual love and companionship are in. There’s no consistent way around that.

Adam and Steve will just have to find another way to pass on their wealth and control their women. Let’s face it, they still have plenty of opportunities for doing so.