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The same-sex marriage debate has been raging in Australia for over a decade, but the polemics have never been as furious as they are now. Supporters and opponents of same-sex marriage agree on at least one thing: the decision that voters make will have radical implications for Australian society and culture.

"No" voters -- and, trigger warning, I'm a "no" voter -- argue that fundamental religious liberties will come under threat if the definition of marriage is altered. "Yes" voters see a same-sex marriage as a vital step towards the elimination of social prejudice and hostility toward members of the LGBTIQ community.

While many "yes" voters lampoon the apocalyptic rhetoric of the "no" campaign, the reality is that some of more extreme proponents of same-sex marriage are mooting radical changes to federal anti-discrimination laws.

While truth-talk has almost entirely disappeared from discussion, I feel confident enough to make one truth claim, and it is this: we have lost the ability to meaningfully disagree in the marriage debate.

From a debate that was at least minimally civil, public discussion has descended into a vicious and sardonic ideological shouting-match. Opponents of same-sex marriage risk social ostracism for daring to express ambivalence towards the proposed changes. Same-sex marriage has gone from being a thought-bubble of fringe politics to what some commentators now label the "greatest civil rights challenge of our time." Meanwhile, Alt-right political movements are attempting to harness minority dissent and use it to peddle hardline immigration and assimilation policies.

So, how on earth did we get here?

Some commentators attribute the collapse of discussion to divisive tactics of the LGBTIQ lobby and the "Christian Right." LGBTIQ activists have selectively targeted high-profile supporters of traditional marriage and attempted to tarnish their professional reputation and community standing. While I feel that accusations of bigotry and prejudice levelled at the Christian Right are grossly exaggerated, the denizens of the Alt-Right are wont to mix traditionalist sentiment with ultimately prejudicial attitudes towards members of the LGBTIQ community. I'll concede at least that much.

Yet it would be naive to attribute the erosion of meaningful discourse to the use of standard political tactics. The problem with this debate runs far deeper than that.

While I'm no expert in discourse analysis, I've read the work of few scholars who are. And one who is particularly relevant to this debate is the philosopher Alasdair MacIntyre. In his influential treatise After Virtue, MacIntyre argued that the interminable character of modern moral discourse can be attributed to a handful of basic flaws in our approach to public moral debate.

First, MacIntyre argues that the normative concepts we use in ethical discussion are "conceptually incommensurable." That is to say, the premises used in contemporary moral arguments are so radically different that "we possess no rational way of weighing the claims of one against another."

In the context of the marriage debate, we only need to think of the competing appeals to "equality" versus"tradition." Close analysis reveals an endless cycle of assertion and counter-assertion over whether "marital equality" is more important than "the sacredness of marriage." The sad truth is that we can't even get to the question of whether our shared values lead us in one direction or another. Beyond the veneer of mere semantic similarities, the two conflicting viewpoints have no shared ethical vocabulary. Different utterances such as "love is love," "marriage rights are human rights" and "every child deserves the right to a mother and a father" cannot be meaningfully weighed against each other.

The Christian agapeic notion of love, for example, is fundamentally different to the sentimentalist account of love inherent in gay rights narratives; and any Natural Law account of rights directly conflicts with the presuppositions of the constructivist account of rights presupposed by so-called "marriage equality."

The second insight MacIntyre offers is that, while our assertions are typically expressions of interests or preferences, our arguments have a deceptively "impersonal" character to them. Our arguments presuppose "the existence, independently of the preferences or attitudes of speaker and hearer, of standards of justice or generosity or duty." The sorts of claims that we make in public discourse - "it is compassionate to x" or "you have a duty to y" - send us on a wild-goose chase in search of an illusory theory of compassion or standard of duty, when all the speaker is really saying is "I like such-and-such" or "I dislike such-and-such."

This is not to say that there is no such thing as "virtue" or "duty" or "the good." This is only to say that our utterances aren't typically aimed at picking these things out; they're typically aimed at expressing our interests and preferences.

A phrase like "Australia should not legalise same-sex marriage" can have a variety of meanings. Yet when uttered in our current torrid political context, it typically can be parsed as a mere "boo to 'yes' voters." And when politicians tell their electorates that a vote for same-sex marriage is a vote for "love, equality and freedom," the tricolon is more an indication of the strength of their personal interests rather than any meaningful value-claim. Ironically, conservative commentators will respond by attempting to offer an alternate theory of love, equality and freedom, only to discover to their dismay that their interlocutor is not really concerned with developing a rigorous philosophical glossary of terms.

The third - and, perhaps, most interesting - insight from MacIntyre is that the "the conceptually incommensurable premises of the rival arguments deployed in these debates have a wide variety of historical origins."

It is tempting to place the current push for gay marriage within the context of a broader twentieth-century civil rights narrative. But the reality is that the origins of the gay rights movement are heterogeneous (and this is reflected in tensions that frequently surface within the ostensibly united LGBTIQ lobby). On the one hand, contemporary gender theory (pioneered by theorists such as Judith Butler and Julia Kristeva), and more broadly, the Critical Theory movement, a la the Frankfurt School, have provided the conceptual framework for contemporary gay rights and transgenderist discourse.

Yet in current Australian debate, disparate political ideologies have become strange bedfellows (no pun intended): Libertarians such as David Leyonhjelm emphasise the individual rights at stake in the marriage debate, and moderate members of the Liberal party see marriage equality as part of a broader small-government philosophy. Second-wave feminists, while being fiercely opposed to the idea of eliminating the very category of femininity, nevertheless support marriage rights for lesbian women.

A similar story could be told for the unholy marriage of socially conservative Christians and divisive Alt-Right politicians. I will, however, leave this task to other commentators with a keen interest in deconstructing the edifice of conservatism in Australia. Suffice to say that, even if we were to identify the various premises of our competing views on marriage, we would still be faced with a monumental archaeological task of trying to understand the true genesis of our moral terminology. We would need, in the words of MacIntyre, to attempt to understand "the larger totalities of theory and practice" in which our concepts "enjoyed a role and function supplied by contexts of which they have now been deprived." This might get us some way to discovering why appeals to "family values" ring so hollow in a post-modern, post-truth culture.

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Bertrand Russell once wrote that "the essence of a good marriage is respect for each other's personality combined with that deep intimacy, physical, mental, and spiritual, which makes a serious love between a man and a woman the most fructifying of all human experiences."

Rather than telling readers that that you should all vote "no" in the postal vote, I want to propose something even more countercultural. I propose that you go and have dinner with a couple who have been happily married for a good a number of years. By hearing the narrative of a successful heterosexual marriage, you might get some insight into why "no" voters feel so passionately about maintaining the traditional definition of marriage.

Even better, perhaps you can sit down and watch the maelstrom of a young couple having dinner with their kids. As mum and dad clean up the splattered baby food and placated the fighting toddlers, you might start to see the bizarre yet compelling reason why people think that a binary family unit matters.

And - at the risk of committing a secular humanist sin - you might want to attend a religious wedding ceremony. The fundamental spiritual energy that has animated the institution of marriage over the millennia is key to deciphering why a "no" voters reject the attenuated vision of marriage being presented in the current debate.

Xavier Symons is a research associate with the Institute for Ethics and Society at the University of Notre Dame Australia. This article has been republished with permission from ABC Religion and Ethics.