The other day, Chris Daly of the University of Manchester published a piece at Aeon under the headline “Why Doesn’t Philosophy Progress from Debate to Consensus?”

Professor Daly first discusses Thomas Kuhn’s challenge to the idea that science makes progress, limiting himself to the qualified response that, whatever the limits of science, it certainly seems to have produced a great deal more consensus among its devotees than has philosophy. I do wish Professor Daly had gone into greater depth on this point. After all, even the most restrictive definition of philosophy would have to include Plato and a more or less continuous line of thinkers from Plato’s day to ours. That gives you an enterprise that was ongoing for over two thousand years before anyone had heard of the idea of progress. It seems likely that philosophy will persist for thousands of years after that idea is forgotten, unless the human race manages to liquidate itself in the meantime. Kuhn’s model, in fact, would seem to warrant a hope that science, like philosophy, will be compatible with an understanding that all that happens over time is that you get more of some things and less of others, and in any given era the set of things that are decreasing and the set of things that are increasing will both include a mix of good and bad. On Kuhn’s account, neither science nor philosophy is dependent on a belief that history goes in a specific direction and that that direction is a desirable one.

Professor Daly goes on to list five answers traditionally given to his question:

1. “Challenge the pessimism” by giving examples of philosophical problems that have been solved. The example which Professor Daly gives, and about which he expresses reservation, is Noam Chomsky’s claim that Newton solved the mind-body problem by positing the Force of Gravity. For Descartes, two things could not interact with each other unless they had a point of contact, and they could not have a point of contact unless they were composed of the same substance. Since mind and body seem to be different in substance, he could not explain how they could interact. By describing gravity, Chomsky argues, Newton showed that objects could interact without contact. This not only sweeps aside the proposition that bodies cannot interact without contact, but shows that there are no bodies at all in Descartes’ sense. It thereby dissolves the problem.
   
   Professor Daly objects that this argument only defeats Descartes’ definition of body. Physical entities do in fact exist, and mental phenomena do in fact seem to be radically different from them. So there is still a mind-body problem, even if it is not logically equivalent to the problem Descartes described.
   
   I would also object that Chomsky’s proposal ignores the history of the question. Whether there can be interactions among entities that are made of such different stuff that they cannot touch each other was precisely the issue when the Stoics and Epicureans argued with each other about whether humans, who are made of atoms and are therefore mortal, and gods, who are immortal and must therefore be made of something altogether different from atomic matter, can affect each other. Against the Epicurean claim that a collection of atoms could never come into contact with whatever the gods would be made of, the Stoics appealed to the laws of nature as a medium through which gods and mortals could influence each other without contact. Newton’s triumph over figures like Descartes and Spinoza repeated a battle won sixteen centuries before by Posidonius and his associates.
   
   If I were to give an example of a problem that philosophers had managed to solve, I would probably mention Gödel’s Incompleteness Theorem. That some mathematicians nowadays claim that side of Gödel’s work as exclusively their own, insisting that it is separate from the philosophy of mathematics, points to another reason why it often seems that the problems of philosophy are all insoluble- solve one, and people in other fields try to make off with it.

2. Dismiss the issue, and indeed the whole of philosophy, by claiming that “philosophical problems aren’t real problems.” This one doesn’t give Professor Daly much trouble. If the problems were just word-play, it would be as easy to make them go away as it is to solve a crossword puzzle, yet none of the people who make that claim has managed to accomplish such a solution.

3. Claim that “philosophical problems are just much harder than science problems” and therefore take more time to solve. He’s unimpressed by this one, and deals with it in a couple of short sentences.

4. Claim that the classic problems of philosophy resist solution because solving them requires us to do things to which our brains are not suited. Professor Daly calls this an “interesting piece of speculation,” and notes that the limits of human understanding are in fact a topic of empirical research. But he also finds it rather too convenient to say that solving philosophical problems is beyond our ken while “everything else we do in philosophy… is open to us.”

5. Daly’s own position is somewhere to be found in his description of the final option, so I will quote it in its entirety:

The fifth diagnosis, the one I think explains the most, doesn’t single out any one factor to explain philosophy’s lack of progress. Instead, it takes this to be the interaction effect of a cluster of things. As we saw in the case of intuitions, there’s controversy not only about the theories that philosophers devise but also about many of the methods or kinds of data that they appeal to in support of their theories. Also, philosophical problems have ‘entangled’ natures: proposed solutions to one problem require contentious assumptions about other live problems. For example, there’s a problem in saying what morality is about – what it is for actions or people to be morally good or bad. But this problem is not compartmentalised. Accompanying this problem about the nature of morality, there’s a problem about why we should accept some moral views rather than others. And, as we’ve seen, there’s also a problem about why anyone should care about morality. So, we have a nest of problems here: a definitional problem (what is morality?), an epistemological problem (how can we tell what’s moral?), and a motivational problem (why does morality matter?). Solutions to these problems will make assumptions about reality and our minds that raise fresh problems of their own, and so the issues ramify.

I’m a bit leery of Professor Daly’s emphasis on ethical theory- I am inclined to think that ethics is acceptable only as a subfield of epistemology. Lose sight of what humans can know and how they can be said to know it, and you quickly drift into the realms of theodicy.