David Hume and the limits of philosophy

Last week was the tercentenary of the birth of David Hume, the great Enlightenment philosopher, whose most famous idea is that “reason is, and ought only to be, the slave of the passions”. That’s an extraordinary statement, if you think about it, coming in the middle of the Age of Reason. Have we misnamed that period? Should we call it the Age of Passion?
Hume was one of a group of 18th century philosophers who, in some ways, turned philosophy on its head. The assumption in ancient philosophy was that reason is the divine part of us, while our passions are lower, bestial impulses that have to be controlled, or even completely removed. The passions were seen, by most ancient philosophies, as sicknesses of the soul - the word pathos actually means suffering or disease. The medicine for this sickness is philosophy. You practice overcoming your passions using a variety of philosophical exercises, until you eventually arrive in a state of perfect apatheia (emotionlessness) and ataraxia (tranquility), in which you simply observe the Cosmos, nodding, and murmuring ‘Quite so!’

The Sentimental Philosophers of the 18th century - Hume, Adam Smith, Shaftesbury, Mandeville, Rousseau and others - argued by contrast that humans are driven by their sentiments, their emotions, their passions - and they argued this was all-to-the-good, because without our passions we would never have the motive to do anything (emotions put us in motion), and also because, often, our passions have indirect pro-social benefits. For example, Hume was candid that his ruling passion was a desire for literary fame. But this motivated him to work very hard and to create works that benefitted his society. So his passion had a prosocial outcome, although this wasn’t his primary motive.

Both Hume and Smith made the emotions the basis of their moral philosophy. We don’t reason our way to ethical judgements using some detached philosophical thinking, they argued. Rather, we observe an action, and feel instinctive sympathy, or approval, or disgust. In this, they anticipated the social intuitionist psychology of Jonathan Haidt or John Bargh, who argue that we judge the world through gut feelings and intuitions, which our reason then rationalizes after the fact.

Hume was very sceptical of ancient philosophies like Stoicism, Platonism and Epicureanism, because they were varieties of self-help - they championed the idea that we can use our reason to change our emotions and re-make our personalities. This seemed wildly over-optimistic to Hume.

He wrote:

The fabric and constitution of our mind no more depends on choice, than that of our body...As a stream necessarily follows the several inclinations of the ground on which it runs, so are the ignorant and thoughtless part of mankind actuated by their natural propensities. Such are effectually excluded from all pretensions of philosophy, and the medicine of the mind, so much boasted. But even upon the wise and thoughtful, nature has a prodigious influence; nor is it always in a man’s power, by the utmost art and industry, to correct his temper, and attain that virtuous character to which he aspires. The empire of philosophy extends over a few, and with regard to these, too, her authority is very weak and limited.

Philosophy is, for Hume, not some magic medicine, but rather a fun and harmless past-time that some rare personalities happen to enjoy. The masses, meanwhile, need a stern Tory government to keep them in line. It’s quite a bleak view of philosophy for one of the leading philosophers of the Age of Reason. And I happen to think it’s wrong. I think we can re-programme our passions using our reason, in those instances when our passions threaten our well-being. I think it’s very laborious and energy-intensive, but I think it is possible, when the alternative is a life of complete misery.

The success of reason-based therapies like CBT, which was inspired by Stoic philosophy, suggests that the Greeks weren’t as naive as Hume thought. In fact, our society is full of people who became enslaved by emotional disorders like depression, and who managed to reason their way out of them using rational philosophical therapy.

This isn’t exactly using reason to ‘overcome’ the passions. Rather, it’s using reason to steer our natural desire for happiness in more intelligent and sophisticated directions. Of course, without the strong natural drive for happiness, love and belonging, our reason wouldn’t have anything to steer. So philosophy is not ‘against’ the emotions - rather, it involves the education of the emotions.

And I think this education is open to almost all of humanity. I would argue that philosophy at its purest is the capacity to ask yourself questions about your beliefs, emotions and actions. As such, it’s at the heart of being human. It is “the most excellent human activity” as Socrates put it. And you can train this capacity. You can teach it to people from all sorts of different backgrounds, not just the rich, or geniuses like Smith and Hume.

Hume would probably have chuckled at such naive enthusiasm. The irony is, philosophy was hugely popular in his day. Hume’s works were among the best-selling books of the era, and their success proved the growing popular demand for ideas, and the expanding reach of the ‘empire of philosophy’. The ideas of philosophers like Hume, Smith, Rousseau and Bentham had far more influence on society then than any philosophers today. So it seems strange that Hume should be so downbeat about philosophy’s popularity and impact.

Perhaps it was precisely because philosophy was so popular during the Enlightenment, and because of the era’s enthusiasm for grand philosophical schemes to re-make humanity, that Hume took such a sceptical view. In our own age, when philosophy enjoys no such prestige, we need to bolster the case for its relevance, not temper it.

Want to find out more about David Hume?
* Here's a great Radio 4 documentary on his life and ideas.
* Here is a reading of Bertrand Russell's chapter on Hume from his History of Western Philosophy.
* Here is a Philosophy Bites interview with Paul Russell about Hume's Treatise on Human Nature.
* Here is an account of Hume's death, and the deathbed visit by a young James Boswell, who was curious to see whether Hume would recant his sceptical and agnostic views in the face of death (he didn't).