There is little doubt that one of the legacies to us of the Enlightenment is the idea of thinking for oneself. The rallying cry of the era’s great philosopher Immanuel Kant (1724-1804) was: “Have the courage to think for yourself!” It is pleasant, because so much easier, he noted, to let others do our thinking for us: priests, politicians, social commentators and the like. It is much more difficult to think for oneself. Kant insisted that the necessary condition for such free thought was freedom – freedom to argue, to disagree, to refuse.

Yes, it is easy to point out that there is no such one intellectual movement as ‘the Enlightenment’: those thinkers, writers, poets, essayists and so on whom we think of as making up the Enlightenment actually argued for many very different views: liberal, conservative, religious, atheist and so on. Nonetheless, out of the confusion of intellectual currents that we call the Enlightenment, we can perhaps isolate some the key ideas that have remained with us.

To Kant’s idea of thinking for ourselves we may add our belief in equal rights and, what goes along with this, tolerance. There may be others, but these are among the central ideas in question. And we tend to see the whole package of ideas as a victory over superstition and myth, congratulating ourselves therefore at the same time for being rational.

Some 75 years or so after Kant’s essay, the great English liberal John Stuart Mill (1806-73) wrote his noble work On Liberty in which he argued for the right of any individual to think and act as he pleases on condition that he not harm anyone else. I call the work ‘noble’, and it is, because Mill demonstrates an intense respect for his fellow human beings in the work, and a belief in moral, social and political progress if you set human beings free. But his noble attitude concealed what is surely a form of naïveté. Mill thought that free individuals would naturally gravitate towards that which he took to be high culture: poetry, philosophy, literature and the like. It did not occur to him that they might naturally want that which is cheap, shallow and vulgar.

That was pretty much all Nietzsche (1844-1900) saw in liberal ideas of freedom of thought and action. We have become, he thought, ‘herd animals’, more or less totally incapable of thinking for ourselves. Dostoyevsky (1821-81) had already suggested that human beings tell themselves that they want freedom but do not really want it, because it makes life too complicated: better the easy life of falling in with what everyone else is doing.

Countless thinkers have echoed and developed the kind of philosophical and cultural critique developed by Nietzsche and Dostoyevsky, one of the latest being that of the Italian linguist and cultural critic Raffaele Simone (1944- ) who, drawing on Tocqueville (1805-59), has argued that we have abdicated serious engagement in political life and turned ourselves over to being dominated by what he calls ‘the gentle monster’: our political masters and their cronies keep us acquiescent by turning the public space into an arena of spectacle, fun and entertainment, and, because we enjoy this mindless slavery, we are complicit in the whole thing.

It is hard, I think, not to see some truth in such critiques. And I doubt very much that we are generally capable of thinking for ourselves any more than were those of the past. Probably there are some, a very few wise or original people in any age, and the rest of us are just hacks, thoroughly second-hand in the way Strindberg (1848-1912) said the characters of his plays were: ‘agglomerations of past and present cultures, scraps from books and newspapers, fragments of humanity, torn shreds of once-fine clothing that has become rags, in just the way the human soul is patched together’. The idea of thinking for oneself, whilst a moving idea, seems not to fit very well with the frailties of the human condition.

To these reflections we may add the point that contemporary ideas of equal rights have their roots in Christian thought and probably cannot be justified without recourse to God. And then there is the fact that our belief in tolerance depends very largely, not upon philosophical justifications, but on our location in a European culture that had virtually exhausted itself in a frenzy of self-destruction and, weary of conflict, simply had to find some way of getting by without devouring itself.

Even more worrying is the fact that it is arguable that, whatever else we make of the Enlightenment as a movement, we cannot wholly dissociate it from being in different ways implicated in, or in part leading to, various forms of violence, such as that carried out by the Jacobins in the French revolutionary period, or the Nazi death camps which, as Adorno (1903-69) and Horkheimer (1895-1973) sought to show, embodied Enlightenment notions of instrumental reason and science that seek to dominate nature, the nature of human beings, and thus human beings themselves.

Our Enlightenment ideas, it seems, turn out to be hollow, or dependent on forms of justification that most can no longer accept, or implicated in violence.

From this point of view the whole idea of Enlightenment is itself some kind of fantasy or myth. We like to tell ourselves that we are more rational than were our ancestors, and that this is the product of the Enlightenment, but there is, after all, nothing particularly rational about the life we lead, one in which we attach great value to material security, a long life and freedom from pain. There is nothing irrational as such about depriving some individuals of their freedom, or intolerance, or belief in the natural inequality of human beings. We might find these things unreasonable, but that just means that, by our lights, these things are morally unacceptable or abhorrent. That does not make them irrational.

I am not arguing for relativism. Rather, I am saying that our ideas of liberty, equal rights and tolerance are the contingent upshot of history, but that we try to justify them in ways that turn out to be inadequate. Both relativism and its opposite are failures to engage with the reality that we have to learn to find some way of living with our genuine commitment to values of tolerance and the rest without having the kind of proof or foundation for them that we would like. And that means, without the kind of proof or foundation that we like to suppose the Enlightenment gave them.