“All three of the greatest Greek philosophers, Socrates, Plato, and Aristotle, regarded homosexual conduct as intrinsically shameful, immoral, and indeed depraved or depraving. That is to say, all three rejected the linchpin of modern ‘gay’ ideology and lifestyle…”

This is how Oxford-based philosopher, John Finnis, argued solemnly in his 1994 essay, ‘Law, Morality, and ‘Sexual Orientation’’. You will be excused for rolling your eyes at the use of ‘gay lifestyle’ and the fact that ‘sexual orientation’ is put in scare quotes.

But some people went further than that. Last month, more than 600 students and staff at Oxford signed a petition calling for Finnis to be removed from teaching duties. This episode involves more details than can be adequately addressed in this article: such as whether academic freedom covers retired faculty and whether it protects non-contractual teaching activities.

It’s also difficult to make a meaningful contribution to the already cliché and polarised debate of free speech. What I find interesing is the fact that the two sides of this debate share a surprising and often-ignored common ground.

Those who are critical of the Oxford students often argue that participants in conservation should learn from each other and that’s why deeply disagreeable speech should be tolerated. They sometimes also make the case that the best way to convince those who one disagrees with is through speech, and therefore suppressing speech is counterproductive.

In a similar vein, proponents for imposing limits argue that some speech is so grotesque that there is no value to them. What both sides agree on is that free speech only covers something if engaging with it produces positive value. A speech can have value because either its contents contribute to the marketplace of ideas or that the engagement itself brings about the greatest value among all available alternatives. We can call this view the positive justification for free speech.

The problem with this view is two-fold. One is epistemic. It’s often tricky to antecedently adjudicate whether a speech that one deeply disagrees with has any value. There is also the more significant principle problem. It can seem inappropriate to hold that speeches we do tolerate all have some positive value to them — think, for example, climate denial, white supremacy and religious fundamentalism. Unless one is willing to bite the bullet and accept that all of these should be criminalised, one is left concluding that there is somehow something positively good about engaging with these speeches.

The positive justification for free speech can be inappropriate not only because it contends that all speech we do tolerate brings some positive good; it also draws an inappropriate and potentially untenable line between the speeches that we do tolerate and those that we do not. Most who endorse relatively extensive limits often only argue that a teacher who espouses racist views should be fired; few go as far as advocating that those who champion lower taxes or dismantling universal healthcare should be subject to the same treatment. But it is at least not clear that engaging with the latter policies will be more productive, given that they can — in some worldviews — do as much harm to those whom they affect.

Again, there can be rejoinders; some of them might be satisfactory. So be it. My point is that the issues I raised above, at least on the face of it, give us some reason to consider an alternative justification for free speech.

On this alternative view, the negative justification, free speech is not contingent on and cannot be wholly explained by the positive contribution it may make. People have free speech, to use an often-ambiguous term, because they have a right to it.  Of course, there is a further question as to what grounds such a right. To give an example, ‘contractualists’, as they are commonly known, argue that people have a right in general, and therefore a right to free speech, because this is something that cannot be reasonably rejected.

Nevertheless, the distinct character of negative justification (as per Rawls) is that it is formal and not substantive. That is, the negative justification presents only formal criteria which identify what kinds of speech should be limited; and it is not substantive in the sense that such formal criteria, ideally, will not be reasonably rejected no matter what one’s substantive commitments are. To put it in a less abstract language, most people — progressives and conservatives — would agree that shouting ‘fire’ in a crowded theatre should not be protected by free speech.

Moreover, this doesn’t mean that free speech should only be restricted in instances where people with diverse substantive commitments can readily agree on. For example, one can plausibly make a case that speech should be limited in cases where it impacts on its audiences in certain ways. There can then be further discussion on what sorts of impact justify imposing limits. The key is that such discussion should pay no regard to and remain neutral among a diverse range of substantive views.

To be sure, there are difficult questions plaguing contractualists and by extension, those who advance a negative justification for free speech. The chief among these concerns is whether there exist things that people cannot reasonably object to, and what happens if we disagree about what can be reasonably objected to.

Nonetheless, this view allows for the possibility that we can tolerate a wider range of speech without necessarily making any substantive judgements about them. Namely, it allows us to hold that some speeches should be protected even when we are hesitant to ascribe any positive value to them. This, I believe, is a desirable implication.

As for the case of Finnis, I am inclined to think that his published views, albeit being deeply objectionable, should be protected by free speech. At the same time, I also tend to disagree with the insistence that students should necessarily engage with him or debate him. As Sophie Smith succinctly puts it in her London Review of Books commentary, “[w]hen I read my straight colleagues telling everyone else to give Finnis the ‘respect’ of engaging with his opinions, to ‘make arguments’ in response, I wonder how many times they have had to ‘make the argument’ for their happiness, for their home and their partner, for the life they’ve built with the people they love. At times, I’m not even sure what I am meant to be making the argument for…”

As a gay man myself, I share Smith’s sentiment all the more profoundly. The thing is – at least this is what I hope to show – that we can let people speak even when they might have nothing valuable to say.