“Since science took its modern form in the seventeenth century, it has been one long success story.” By contrast, we philosophers “don’t seem to have progressed much in the two and a half millennia since Plato wrote his dialogues.” That’s the conventional wisdom, as described by David Papineau (King’s College London) in The Times Literary Supplement. But if there’s one lesson in philosophy, it’s that the conventional wisdom isn’t the whole story.

Papineau thinks that philosophy is “a route to truth,” but takes up the reasonable question: “where’s the progress?” He mentions the “spin-off” theory, according to which

the supposed lack of progress in philosophy is an illusion. Whenever philosophy does make progress, it spawns a new subject, which then no longer counts as part of philosophy. In reality, philosophy is full of progress, but this is obscured by the constant renaming of its intellectual progeny.

But that isn’t the whole story, he says. Philosophy still has plenty of its own questions, including ones that have been with it for millennia.

Getting clear on why philosophy’s progress is slower than that of the sciences depends on getting clearer on the differences between philosophy and science. Here’s the crucial one, says Papineau:

The real difference between philosophy and science is not subject area, but the kind of problem at issue. Philosophical issues typically have the form of a paradox. People can be influenced by morality, for example, but moral facts are not part of the causal order. Free will is incompatible with determinism, but incompatible with randomness too. We know that we are sitting at a real table, but our evidence doesn’t exclude us sitting in a Matrix-like computer simulation. In the face of such conundrums, we need philosophical methods to unravel our thinking. Something is amiss, but we aren’t sure what. We need to catalogue our assumptions, often including those we didn’t know we had, and subject them to critical analysis.

This is why philosophical problems can arise in scientific subject areas too. Scientific theories can themselves be infected by paradox. The quantum wave packet must collapse, but this violates physical law. Altruism can’t possibly evolve, but it does. Here again philosophical methods are called for. We need to figure out where our thinking is leading us astray, to winnow through our theoretical presuppositions and locate the flaws.

It should be said that scientists aren’t very good at this kind of thing. They are much happier with what Thomas Kuhn called “normal science”, working within “paradigms” of settled assumptions and techniques that allow them to focus on issues that can be settled experimentally. When they are faced with a real theoretical puzzle, most scientists close their eyes and hope it will go away.

Progress in philosophy may be slower than that in the sciences, but this is to be expected, given the difficulty of the questions it takes up:

Most people don’t enjoy banging their heads against nasty paradoxes. It’s a dirty job, but someone has to do it. Given this, it is unsurprising that philosophical problems aren’t easy to settle. The difficulty of philosophy doesn’t stem from its peculiar subject matter or the inadequacy of its methods, but simply from the fact that it takes on the hard questions.

You can read the whole of Papineau’s essay here.