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The World in Kant’s Head

by Rick Lewis

“Our age is the age of criticism, to which everything must submit. Religion through its holiness and legislation through its majesty commonly seek to exempt themselves from it. But in this way they excite a just suspicion against themselves, and cannot lay claim to that unfeigned respect that reason grants only to that which has been able to withstand its free and public examination.”
Immanuel Kant, Critique of Pure Reason, 1781

In many ways, Immanuel Kant was a man for our times. The bewigged eighteenth century thinker sat at home for years, reading and writing, taking a walk once a day, barely ever travelling more than a few miles from his home town, yet he tried to set down some universal truths about what we can know, what people are, and how we should all live. Innumerable people today, hunched in the glow of their computer screens, try to do all that on Twitter, but one difference is that Kant was extremely good at it. He dug deep – deeper than a mole in a coalmine – trying to tunnel under the barriers that the universe has erected to hide itself from our understanding. An indication of his success is that his ideas seem to become more, not less, relevant as the centuries go by.

Kant was born in the East Prussian city of Königsberg, and lived there all his life. He worked as a private tutor for years before finally, in middle age, gaining tenure as a lecturer at the university. He didn’t even start publishing his best stuff until he was 57, which is a consolation to some of us, and after that the works just poured out of him. He had far too many groundbreaking ideas to discuss in a single article, or even in an entire themed number of Philosophy Now, which is why we are returning to him again in this issue.

One example of Kant’s contemporary relevance is a very short essay he published in 1795 called Perpetual Peace. He started it with an anecdote about the origin of its title:

“Whether this satirical inscription on a Dutch innkeeper’s sign upon which a burial ground was painted had for its object mankind in general, or the rulers of states in particular, who are insatiable of war, or merely the philosophers who dream this sweet dream, it is not for us to decide.”

Hence this issue’s front cover by Steve Lillie showing Kant in a cemetery. Clearly Kant didn’t agree that perpetual peace is only possible for the dead, as his essay puts forward a whole set of recommendations for avoiding future wars. It was a remarkable document for its time, and in some ways laid foundations for the liberal, internationalistic, rule-governed world order that has faced such a test over the last three months. And as Matt Qvortrup explains in his article, this wasn’t Kant’s only venture into political philosophy.

The other essays in our Kant special section deal with two of the main areas of his philosophy. First, in his Critique of Pure Reason (1781), Kant theorized that there are certain facts about the contents and structure of the inside of our heads that you can establish even before you whip out a scalpel or plug in some hi-tech medical scanner. For while Kant agrees with early modern empiricists like Hume that there could not be any knowledge without experience, he performs a ‘Copernican Revolution’ in that he argues that experience itself, and consequently the content of our knowledge, is shaped by the way our human minds work. In other words, the world we experience is always a human world. For more on this see the articles by Thomas Morrison and Joshua Mozersky.

That was pretty clever, but if anything he surpassed it a few years later with two books applying parallel methods to ethics. These were the Groundwork for the Metaphysics of Morals (1785) and the Critique of Practical Reason (1788), in which he develops the ‘categorical imperative’. He defines this in several different ways, as you’ll read in the articles by Matt McManus and Samantha Neave, but his basic conclusion is that we have a duty to act as if our actions are setting a standard for the whole world, and that we should therefore treat other people as ends in themselves, not merely as means to our own ends. Kant’s duty-based system of ethics has been massively influential on subsequent moral philosophers, and is still, after over two centuries, one of the three main secular approaches to ethics, along with consequentialism and virtue ethics.

In recent years, one topic right at the centre of philosophy has been the nature of consciousness, and the question of how consciousness arises in what is presumably a physical universe of causes and effects. It seems surprising that Kant hasn’t been invoked more often in those debates, given his careful investigation of how the human mind must be organised in order to make sense of the world. Maybe we’ll hear more of this in the future, giving us cause to wonder anew at the amazing insight of the old guy with the grey wig.

This is our 150th issue of Philosophy Now. It is 31 years and one pandemic since it was launched, but our aims are unchanged – to entertain and inform; to open up the long and fascinating conversation of philosophy to all comers; to enable professional philosophers to engage with thinkers in other walks of life; and to share a few jokes with likeminded people. Thanks for supporting our efforts, and we hope you enjoy this issue.

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