How (Not) to Know Stuff

Making the climb

One of the most important events of my professional life was also one of the most embarrassing.

In my previous role, I got to speak with some brilliant thinkers. One who was particularly formidable, yet somehow also especially jovial, was the philosopher of knowledge Esther Meek. In fact, Meek was so affable and good-humoured that I began to lose track of time.

What brought me back to earth was when, after we had been speaking for over an hour, at 8pm in her local time, Meek responded to one of my questions by pointing out that I had finally raised what was initially intended to be the entire topic of our discussion. She maintained her generosity throughout the entire almost-two-hour conversation, and I’m grateful, because it was eye-opening.

At thirteen, Esther had found herself wrestling with two questions: How do I know that anything exists outside my mind, and How do I know that God exists?

The first probably reflects a mind unusually prone to philosophising.¹ But the second question is almost universal. And both can easily keep you up at night.

Intellectual Quicksand

Last time I wrote that the person who asks, “Why believe anything at all?” has in one sense simply misunderstood the nature of humanity and/or the nature of belief. But I also hinted at another sense — one with a vexing intellectual history, and one which can easily become a sort of intellectual quicksand.

We could also ask why anyone should believe any particular thing at all, or the similar question, which Meek discovered in her youth and which essentially amounted to, ‘How do I know anything at all?’ What grounds our belief in the things we think we know?

If you are a normal person and less prone to existential crises than those of us who are excessively philosophical, this may strike you as a strange, disturbing or silly question. Maybe it is all those things; but I don’t think it’s an easy question to answer. The core issue is that it’s relatively easy to undermine one’s own justification for believing anything.

Think of a belief which you know is straightforwardly true. Here are a few beliefs I currently take to be true:

1. I am sitting on a bench in a park.

2. When I arrived, the bench was wet.

3. Amusingly, a plaque is fixed onto the bench with the words, “I’m sorry”.

Why am I so confident these things are true? Well, I believe

- the first on the basis of my empirical senses (especially sight and touch)
- the second on the basis of my senses and my memory
- the third on the basis of my senses, my memory (I am not currently looking at the plaque) and my ability to read English

If I were to tell a friend about this situation, they would believe me, because it’s not a farfetched situation and because they’ve (hopefully) found me to be generally trustworthy. But in doing so, they would be relying on my testimony, their memory and interpretation of our previous interactions, and their analysis of the components of my story (e.g. it’s coherence with their prior beliefs).

But how do I know that my empirical senses are reliable? How do I know the universe wasn’t created five minutes ago with the appearance of age and memory? The point is that it’s much easier to undermine someone’s belief in the trustworthiness of their senses, memory, interpretations, etc., than it is to rebuild that belief. The point is that pure scepticism — about anything — is easy. It’s like sliding all the way down Mount Everest: it’s the climb back up that’s hard.

Certainty and Scepticism — Two Solid Attempts

So, given the opportunity, what question did I pose to one of the world’s leading thinkers on the intersection of knowledge and faith?

In her work, Meek very briefly traces the history of the theory of knowledge, arguing that it tends to oscillate between atmospheres of certainty and scepticism (which are probably two sides of the same coin). The ultimate example of focusing on scepticism might be David Hume, while the ultimate example of focusing on certainty might be Rene Descartes.

Two nerds looking like nerds: Descartes (left) and Hume (right).

Neither approach works.

You probably know the phrase, “I think, therefore I am”, by which Descartes meant that the only fact that he couldn’t doubt was the fact of his own existence. If he didn’t exist, who was doing the doubting? This was the first step in Descartes’ quest to build a worldview from the ground up, with absolute certainty at every stage.

This is generally my instinctive approach. For Descartes it stemmed from a particular religious and philosophical climate, and I’m sure it does for me to some extent as well. But I’ve reflected recently that it probably also stems from a personal desire to avoid the risk of being wrong.

Alas, everyone agrees that Descartes failed in his quest to build a worldview on absolutely certain foundations, and no one has succeeded since. To point out just one issue, one of the places where Descartes directed his radical doubt was the reliability of reason and intuition. But how can someone rebuild certainty in their own reason, when they have called into question the very capacity for intellectual progress?²

Pure scepticism is like sliding all the way down Mount Everest: it’s the climb back up that’s hard.

If you doubt everything, you have nothing to build with. As one philosopher put it, “Anyone who knows anything necessarily knows many things. Our knowledge forms a body, and that body has a structure: knowing some things requires knowing other things.”³

So I need to get over my desire for absolute certainty without dependence.

Perhaps the solution is to embrace scepticism? Hume tried it, but his radical scepticism called into question the reliability of induction and science, the reality of causation, the existence of the external world, the perception of moral values, and (again) even the rational process by which Hume argued. (Just a few minor issues.)

So Hume wrote, in a movingly honest passage:

I am bemused by all these questions, and begin to fancy myself in the most deplorable condition imaginable — surrounded by the deepest darkness, and utterly deprived of the use of every skill of body and mind. Most fortunately it happens that since reason can’t scatter these clouds, Nature herself suffices for that purpose and cures me of this philosophical gloom and frenzy, either by reducing the intensity of these thoughts or by some pastime that makes lively impressions on my senses that obliterate all these chimeras. I dine, I play a game of backgammon, I converse cheerfully with my friends; and when after three or four hours’ amusement I turn back to these speculations, they appear so cold, strained, and ridiculous that I can’t find in my heart to enter into them any further.

Here, then, I find myself absolutely and necessarily made to live and talk and act like other people in the common affairs of life.⁴

How not to have an existential crisis, according to David Hume. (I don’t know if backgammon is the way to go though.) [Photo]

Hume couldn’t live the way he thought, and honestly I can relate to that. That might not guarantee that he was wrong to be so sceptical, but it’s certainly not a good sign. And if this approach leaves us completely bereft of confident knowledge, then what good is it anyway?

So what’s the answer? How can Esther know that anything exists outside her mind? How do we ground our beliefs so that our knowledge is reliable but not unattainable? I don’t think the answer is building up from absolute certainty. And I don’t think the answer is embracing absolute scepticism.

Thankfully, there are several approaches which seem far less doomed-from-the-start.⁵ I’ll write about those soon, and try to work out the implications, especially for the big questions of life and faith, culture and politics, theism and atheism.

Have a great Christmas.

1. Although advancing technology is making the ‘Simulation Theory’ a more prominent discussion in philosophical circles.

2. Some argue that the theory of evolution presents a similar challenge for Naturalism, but that’s a topic for another time. If you’re interested, look up ‘Alvin Plantinga’s Evolutionary Argument Against Naturalism’.

3. https://plato.stanford.edu/entries/epistemology/

4. Hume, Treatise of Human Nature, Book I, Part IV, Section VII, p.144

5. I don’t mean to come across dismissive of Descartes and Hume. Both were geniuses, were vastly more impressive than me, and made enormous contributions.