Magdalen College Oxford last night - THINK week.

Wednesday, February 22, 2012
Had an interesting debate with Richard Swinburne, Ard Louis and Peter Atkins yesterday evening as part of THINK week. Richard Dawkins was in the audience and contributed quite a bit. Richard D's dislike of philosophy was apparent again, as was Peter Atkins's, so I was for a while fighting for philosophy alongside Richard Swinburne against Richard Dawkins. Religion was also an issue, though, so Richard S and I were also occasional opponents, with Dawkins, Atkins and myself then on the same team. It was fun, and of course also flattering to be in such prestigious company. There will be a video recording available shortly.

My opening statement (correctly anticipating an anti-philosophical tirade from Peter Atkins) is below, if you're interested (though I did deviate a bit from these notes), followed by a brief comment on Richard Dawkins's subsequent criticism of what I had to say.

I am a philosopher. So it will come as no surprise to you that I am going to argue that philosophy is:

(i) a worthwhile activity, and
(ii) that, for many of the most baffling and important questions and puzzles, the armchair methods of the philosopher, rather than the scientific method, is the right approach to adopt.

Many will of course question this. How, they will ask, can you discover ANYTHING of significance from the comfort of your armchair? To find out ANYTHING about the world, you need to OBSERVE IT. You need to collect data, perform experiments, and so on. And that’s just what philosophers don’t do. So philosophy is a waste of time, concludes Peter Atkins.

Well, I agree that if you want to find out about how things stand out there in the world, the scientific method IS indeed the best method to adopt. You are not going to discover much about reality sitting in your armchair, with your eyes closed, having a think.

But, actually, that’s not to say that EVERY significant question or puzzle is best answered or solved by the methods of science.

Some of the most baffling puzzles and questions are puzzles and questions that would appear to lie outside the remit of empirical science and investigation.

Here’s a simple example. You probably look into mirror everyday. They are familiar everyday objects. And yet they generate a baffling philosophical conundrum – one that baffled Plato back in Ancient Greece, and which philosophers are still writing about today.

The puzzle is this: why do mirrors reverse left to right, but not top to bottom?

You might think – well, this is just a scientific question. If we get in all the data and find out how light behaves, including how it is reflected off a mirror, then we’ll have the answer. But actually, even when all the scientific facts about how light behaves are in, the puzzle remains. Light bounces of mirrors the same way whether it comes in top to bottom or left or right.

The correct theory of how mirrors reflect light provides no solution at all to the mirror puzzle.

So what IS the solution? I think that something like this is correct….

Why do we say the mirror reverses left to right? Because when we imaginatively place ourselves where the mirror version of ourselves appears, we see that the mirror persons left hand is where your right hand is, and vice verse. Yet the head and feet remain top and bottom.

But what if you place yourself where the mirror person appears not be rotating yourself around a vertical axis, but on a horizontal axis. Then your feet would be where your head appears and vice verse, whereas your left hand would remain where your left hand appears.

In short, mirrors only reverse left to right if we take for granted a vertical axis of rotation. Take a horizontal axis, and mirrors reverse top to bottom not left to right. There is no asymmetry. The asymmetry has nothing to with mirrors – it’s generated by what we took for granted – one axis of rotation over another.


(i) this is not a puzzle that can be solved by empirical research.
(ii) It’s a conceptual puzzle that requires a conceptual solution. It’s a puzzle that takes armchair reflection to solve.

So not every puzzle is a puzzle that is best solved by empirical investigation. Some of the deepest and most baffling puzzles can, in fact, only be solved by armchair reflection.

In fact, all sorts of interesting discoveries can be made from the armchair. Mathematical discoveries, for example, can be made from the armchair. They can be achieved by pure thought alone – without doing any data collection or laboratory experiments.

We can also RULE OUT certain hypothesis from the comfort of the armchair.

Suppose an explorer claims to have discovered a four-sided triangle on their travels. Should we mount an expedition to go and check whether this momentous claim is correct? Of course not. We can figure out, from the comfort of our armchairs, that no such triangle exists. Triangles, by definition, have three sides. So a four-sided triangle involves a contradiction. It cannot possibly exist.

This is a rather obvious example. It’s obvious that four-sided triangles are ruled out conceptually. They involve a logical contradiction. But sometimes what is ruled out conceptually is NOT so obvious.

Aristotle claimed that objects of different mass will fall at different speeds. A large, heavy metal ball will fall faster than a small, light metal ball.

Back in the late 16thC, Galileo proved that Aristotle was wrong. Some say he did this by dropping two balls off the top of the leaning tower of Pisa. The two balls landed at the same time. Neil Armstrong did the experiment with a feather and hammer on the Moon

But actually, Galileo probably didn’t perform that experiment. He actually performed a thought experiment – one that he describes in his book On Motion. And of course thought experiments can be run from the comfort of ones armchair.

Galileo reasoned like so…

Imagine two balls, one heavier than the other, connected by a string. Drop this system of objects from the top of a tower. If we assume heavier objects do indeed fall faster than lighter ones (and conversely, lighter objects fall slower), the string will soon pull taut as the lighter ball drags on and slows the fall of the heavier ball. But the system considered as a whole is heavier than the heavy ball alone, and therefore should fall faster than the heavy ball on its own. So Aristotle’s theory, just like the claim that there exists a four-sided triangle, generates a contradiction. Galileo could establish that it is false from the comfort of his armchair.

True, this is a scientist doing a scientific thought experiment, but it illustrates the point that highly significant discoveries can indeed be made from the armchair.

Of course, philosophers need to scientifically literate. Scientific discoveries can be of philosophical relevance. But, at heart, philosophy IS an armchair discipline. And it is none the worse for that.

Philosophy is about conceptual investigation and clarification. Philosophers make conceptual discoveries. I have illustrated how they tackle conceptual puzzles – puzzles that the scientific method just isn’t equipped to solve.

They also probe what we take for granted, our common sense assumptions, sometimes with dramatic results. Philosophers may reveal that what we believe has quite shocking unacknowledged consequences, for example.

This can lead to important breakthroughs. Particularly in moral philosophy. Many of the most important developments over the last couple of hundreds years or so have come about because of philosophical reflection – questioning of, and thinking through the consequences of, some of our most basic moral assumptions and principles.

So philosophy, it seems to me, is not just fascinating, it is also hugely valuable. Blah blah…

Richard Dawkins thought the mirror puzzle and solution was science not philosophy (really? - the last two papers I read on it were in philosophy journals, and I cannot imagine they'd be published in a science journal as they were purely conceptual and involved no empirical claims). Richard wondered why what I do is labelled "philosophy" at all. It's just thinking, he said.

Actually, I don't much care what Richard calls what I do. He can use any label he likes. Relabelling it doesn't mean it's not a legitimate intellectual activity. It seems to be the word that Richard objects to, rather than the activity.