With friends like Stanley Fish, President Barack Obama is not in dire need of enemies. Professor Fish is one of the best-known intellectuals and literary theorists in the US. Now semi-retired, he spreads his wings in his own blog in the New York Times, "Think Again". He can play to the gallery, but his erudite column about pop culture and politics is more like the musings of French intellectuals in Le Monde. This is a role for which he is well qualified, as an acknowledged expert on the 17th century poet John Milton.

I think it is fair to say that Professor Fish is a fan of President Obama. After the inauguration speech, for instance, his column concluded "In the years to come" literary analysis of Obama’s prose "will be expanded and elaborated in a thousand classrooms. Canonization has already arrived."

So it came as no surprise when Fish decided to defend Obama’s attempt to rescind the Federal government’s "conscience rule", which was passed in the dying days of the Bush administration. This allows healthcare personnel to opt out of medical procedures to which they have a conscientious objection. But how he defends it sends a bleak message to defenders of the conscience rule.

Fish is a relativist, a relativist on steroids, perhaps the foremost American relativist since the recent death of the philosopher Richard Rorty. I’m told that he once quipped that now that objectivity is dead, it is no longer necessary to be right; you just have to be interesting. Well, how does an intellectual like Fish deal with the tricky issue of conscientious objection?

Like this: he peels off his relativist T-shirt and puts on totalitarian chain mail. He invokes Thomas Hobbes. Those who are bored to tears with philosophy and philosophers should hang on, for this dusty 17th century philosopher is exceedingly relevant to today’s debates. Hobbes is one of the most important political theorists who ever lived. He is best known for his masterpiece, Leviathan, in which he sketches a quite recognisable portrait of modern totalitarianism.

Hobbes was writing after England had been torn for generations by factional hatred, civil war, and religious persecution. The rack, the gibbet and the axe were common. Strong central authority was needed to keep restless subjects in order. And the biggest danger to the social order was religious strife. Leviathan – an all-powerful government with no separation of powers – was needed to handle dissenters.

Hobbes had an odd notion of "conscience". By it he meant private shared knowledge, as opposed to public knowledge. There was no right to act on one's conscience, he said, because this would put public order at risk. Somewhat unexpectedly, relativist Stanley Fish feels much the same. Conscience is a private voice whispering what is right and wrong. Obeying this rather than government directives leads to disorder and even anarchy. Thus, says Fish, "obligations vary with different contexts and that one can (and should) relax the obligations of faith when one is not in church". In fact, he states bluntly that "This sequestering of religion in a private space is a cornerstone of enlightenment liberalism". Does this mean that American democracy will be upended if a few doctors and nurses refuse to participate in abortions or if a pharmacist refuses to supply a woman with "emergency contraception"? Apparently so.

Of course, "one’s inner sense of what is right" -- which is how Fish and Hobbes see conscience -- does not correspond to the conscience of most conscientious objectors. Rather, they feel that they are following a law inscribed in the nature of things and that it is possible to hold a rational debate about whether this law exists, and whether it applies to this particular case.

But Fish is not interested in debates. He wants conformity. In his argument against conscientious objection, relativism comes full circle: from anarchically asserting that everyone's conscience is right because there is no right and wrong to asserting that in a state of anarchy we have a duty always to obey Leviathan. "Everyone [should] agree to comport himself or herself as a citizen and not as a sectarian, at least for the purposes of public transactions," Fish contends. Argument is pointless, for there is no truth to argue about.

So here’s where Fish’s exhumation of Hobbes becomes relevant. What is going to happen to conscientious objectors when the conscience clause is rescinded? "Obey, or else" is the message that Stanley Fish is telegraphing to them. For relativists like him, democracy itself is at stake, not just women’s rights. I fear that dissenters should be prepared for an iron fist in an iron glove.