If you judged David Hume the man by his philosophy, you may judge him as disagreeable.

He was a Scottish philosopher who epitomized what it means to be skeptical – to doubt both authority and the self, to highlight flaws in the arguments of both others and your own.

By all measures, however, in spite of his fierce attacks on all forms of dogma and certainty, it appears that in his personal life, he was a kind and thoughtful and admirable character. If we follow the trail of words from those who knew him, almost all had wonderful things to say.

Hume managed to accomplish something rare with his philosophy: Not only was it a robust theoretical framework for making partial sense of reality, but it helped him live well, too.

It wasn’t necessarily that he didn’t face his own challenges or that things were always easy for him (he was actually chastised during his time for his non-religious ideas), but somehow, he was able to come out on the other side as someone who could rise above such things.

It’s relatively rare to find historical figures that show this kind of synergy in their intellectual and their personal life, and it’s even rarer for them to be as historically important as Hume.

Some people argue that the philosophical skepticism he applied was of the extreme kind, but if we take a closer look, it’s pretty clear that Hume knew when to balance it with practicality. His life shows how we may learn to do the same by:

Seeing the limits of reason and logic

• Living with conceptual contradictions

• Making judgment as a spectator

Skepticism is intimately tied to the idea of progress, but it’s contingent on a certain balance.

See The Limits of Reason and Logic

Ever since the days of the ancient Greek philosophers, in one way or another, many subsequent thinkers have fallen into two camps of thought: rationalist and empiricist.

This distinction has been more apparent since Rene Descartes helped revive modern philosophy, but the conflict has always existed at the core of our inquiry. In simple terms, it’s an argument about whether knowledge is gained through reason or sense experience.

While there are compelling cases for one, the other, and even both simultaneously, Hume, who was an empiricist, was the first to show the flaws in a purely rationalist model.1

He understood our mental perception of the world as created by two things: ideas (thoughts) and impressions (sensations and feelings). But he made the argument that the ideas could only ever be derived from our impressions, and thus they weren’t ever independent at all.

Beyond that, various mental facilities translate our impressions into ideas, and quite often, this is done in a way that leads us to contradictions and logical fallacies. Even the principle of cause and effect (the bedrock of reason), he argued, could be doubted by mere argument.

We don’t ever observe or deduce something causing an effect, but rather, we fall into habits of thought that are reinforced into us because they anticipate a probabilistic connection.

While Hume understood that in practice the principle of cause and effect was robust enough to rely on, as even he did, his argument made it clear that reason and logic aren’t everything.

In fact, taking it further, he showed how even his own philosophy could be doubted, and how impossible it was to derive any sort of certainty about our conceptual knowledge.

He still stood by his empiricism, but the point was to illustrate how skepticism could poke holes in anything, and how uncertain we really are about pretty much everything.

Live With Conceptual Contradictions

If the hold of skepticism is so strong, the obvious questions naturally arise: How exactly are we supposed to live if we can’t be sure of anything? What’s the point of all of this inquiry?

The point is that skepticism helps us destroy bad ideas so that we can make them a little better. At the same time, however, there comes a time when this kind of skepticism has done its work, and this is when we have gotten to the common-sense ideal of good enough.

In his masterpiece An Enquiry Concerning Human Understanding, Hume famously made this exact point, saying: “Be a philosopher; but, amidst all your philosophy, be still a man.”

This has commonly been associated with an early kind of pragmatism (a philosophy birthed a century or so after Hume’s time) that argues against the notion of seeking absolute truths about reality and its contents and just living in a way that works, practically and meaningfully.

There is some merit to this interpretation, of course, but it’s important to note that Hume still valued the conceptual and the philosophical. He just knew when and where to draw the line.

By using abstract reasoning that isn’t detached from reality and by respecting certain facts, we can make distinctions between right and wrong, and we can live in alliance with them.

But at the end of the day, we all have to deal with a world in front of us that demands a kind of attention that transcends the concepts and ideas that we spend our time thinking about.

Philosophy may give us insight into how best to think, and even some exposure to what kind of life is preferred, but the day-to-day business of living goes beyond mere philosophy.

Unforgiving skepticism is self-defeating. A balanced version of it, however, does have a place. It reminds us to exercise both caution and modesty so that we can actually improve.

Make Judgements as a Spectator

The one domain of philosophy where the conceptual is valuable and that consistently contributes to how we live is the domain of ethics: the study of right and wrong conduct.

Naturally, Hume had a lot to say about ethics. While he was okay embracing an innocent pragmatism in some parts of his life, he did think that there was a moral way to live.2

His argument, again, began from the perspective of an empiricist. He saw reason as being bound by the inputs of sensations and feelings, which meant he denied that rationality could ever on its own motivate us to act in a way that can be considered truly moral.

The root of our morality, according to Hume, is our moral sentiments: We have innately programmed feelings that tell us when we are acting in a way that is virtuous or vicious.

We have an urge to balance our own self-interest with the interest of the group we identify with. And because we care about our group, we can feel sympathy, and thus act morally.

Given that we live in a world in which we interact with more than just our intimate group of friends and family, the test for a moral action is relative to a common point of view.

For example, if you are interacting with another person and there is an unbiased spectator there to witness it, then your actions can be judged to be either virtuous or vicious based on how this sympathetic spectator feels about what has taken place between the two people.

Hume essentially makes the case that this common, unbiased spectator exists within us, too, and that’s why purely selfish behavior, even with a stranger, isn’t in our own self-interest.

If we weren’t self-interested, our ability to survive would suffer. But at the same time, if we are too self-interested, we ignore the fact that we can’t survive without other people, either.

All You Need to Know

It’s often said that philosophy teaches you how to think. But what it doesn’t teach you is how to live. And in practice, they are two very different things with two very different goals.

Even today, David Hume is the thinker that most living philosophers feel they best identify with. He practiced skepticism, but he also wasn’t afraid to stop it from getting in his way.3

A few of his big ideas can be summarized as follows:

I. See the limits of reason and logic. Regardless of whether you identify as a rationalist or an empiricist or both, there is a good case for impressions coming before ideas, and when the former are translated into the latter, there are contradictions and fallacies that arise. It’s a reminder that thoughts have boundaries, and skepticism is a default position.

II. Live with conceptual contradictions. The point of skepticism is to correct problematic thinking that leads to problematic conclusions. At a certain point, however, especially when it comes to the daily business of living, sometimes, something is good enough even if we can conceptually contradict it. Philosophy has a broad reach, and it can teach us a lot about how to live, but ultimately, life transcends thought-games.

III. Make judgments as a spectator. The domain in which philosophy arguably operates most effectively is the domain of ethics. And if impressions come before ideas, then rationality on its own can’t motivate us to act morally. Rather, it’s our moral sentiments, that manifest as a kind of conscience (unbiased spectator), that remind us of when we are acting virtuously and when we are acting viciously.

To doubt is to be human. We learn when we accept uncertainty, and we grow when we self-correct. Skepticism is a state of mind that allows the right kind of doubt to flourish.

It’s easy to see the world as you want to see it. But it takes boldness to try and see it as it is.

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