Most Australians are horrified when they hear how some parents arrange their children's marriages and then get angry, or even violent, when the kids won't play along. The explanation for this is simple: the basis of contemporary marriage is love and affection. The modern "marriage for love" represents a decisive rejection of parental and social control over individual romantic choice.
But before we get too smug about our marital freedom we need to remember that, as things stand, we let the government regulate the gender of the person we can marry. I struggle to see how this is different from parents calling up a marriage broker and choosing their children's spouses for them.
Many heterosexual people choose not to marry. My wife of 30 years and I are among them. We simply do not consider we need a certificate issued by the government to confirm that we are married. No doubt many gay, lesbian, bisexual, trans, and intersex people will choose likewise.
However, when the law says LGBTI people cannot marry, in an important sense it is diminishing their liberty; a major choice is closed off. The state is interfering, telling certain people that they can do what they want, except when they can't (while everyone else, of course, can). As for intersex people, under current Australian law they cannot marry anyone at all.
Throughout history, human societies have had every form of marriage imaginable (including same-sex marriage). Some societies in China had no conception of marriage at all but had a system of raising siblings' children.
Even within opposite-sex marriage, definitional differences over time are pervasive. The use of marriage to retain control over property, including inheritance, was a major concern long before it became a religious matter. Marriage of close relatives, particularly cousins, has wreaked havoc in many societies.
And it took until the 20th century for the status of a married woman in developed common law countries to surpass that of a married Roman woman in the first century AD. The historical diversity is staggering.
Support for marriage equality does not require, or indeed imply, approval of any particular marriage or marriage outcome. Nor does it open the door to bigamy, polyamory or any other dire outcomes that some people predict. It's not as if these will sneak up on us either; to be legal, further changes in the law would be needed, prompting widespread public debate.
Furthermore, marriage equality will not change the situation with respect to adoption of children. Same-sex couples have been able to adopt children for years. Whether children do better with a mother and father is not the question; not all children can have that, but they all deserve a loving, stable home life.
All my Freedom to Marry Bill does is prevent the government from stopping two people from getting married on the grounds that they are not a man and a woman. It's based on the view that people ought to have the freedom to choose their own life path. As John Stuart Mill said, "over his own body and mind, the individual is sovereign".
Importantly, widening the definition to allow marriage equality will do existing forms of marriage no harm, just as no harm was done when Jews could finally marry non-Jews, Protestants could marry Catholics, and blacks could marry whites.
Some in the community place great significance on the institution of marriage. We need to respect that. But those who have a particular view of marriage should not seek to impose their view on others. Not everyone respects that. When my bill was listed for debate this week, both sides in the debate engaged in substantial harassment of senators and members. Moreover, homophobic opponents of same-sex marriage have been calling my office with obnoxious abuse.
If we accept the view that marriage is a private matter between consenting adults, the only choice we each need to make is whether to participate and which variety of marriage to embrace. And for those who perform marriages, religious or civil, there should be no obligation to marry those of whom they disapprove.
My bill requires nothing more than tolerance – a decision to stop minding other people's business.
Senator David Leyonhjelm will present his Freedom to Marry Bill to the Senate on Thursday.