One of the most peculiar features of philosophy, much remarked upon, is that philosophy doesn’t seem to make progress. Not only that, we seem to return to the same views again and again. What explains this?
Philosophers disagree (as usual!), but I’d like to offer a hypothesis with two parts.
(1) Theory Space is Large. The space of plausible philosophical theories is very, very large perhaps because the space of reasons to believe as such is very, very large. As a result, progress in philosophy can go in so many different directions in principle.
(2) Arbitrary, but Real Progress. Consequently, non-rational factors like the social status of leading philosophers play a major role in determining the direction of philosophical progress, but these factors do not imply that there is no progress.
Regarding (1), it is plausible that philosophical theory space is very large, much like the class of mathematical theorems. Concept space is big, and theories that string them together to explain things is also going to be big. Further, philosophers have not only generated a huge range of views, the range of views advocated continues to grow. We’ve never run out of things to say, or found issues where we can’t find any interesting theories. People are always proposing some new, interesting thesis. If concept and argument space is very, very large, that makes sense.
Regarding (2), Why do we land in the particular spaces that we do? Why were so many of us logical positivists fifty years ago, and now we seem to be moving away from even basic philosophical naturalism?
Social Status. My sense is that philosophical discussion is driven in large part by the interests of the highest social status philosophers. I don’t know how to explain their interests, which are perhaps too personal to systematically theorize, but high status philosophers are able to drive discussion because they’re usually quite careful in developing frameworks for asking questions (rather than offering persuasive arguments). And they’re usually good at preparing graduate students to devote their lives, or much of their lives, to those questions. Given the rewards associated with publishing, and the ease with which graduate students can publish on questions where their high status advisors blaze a trail, as well as the benefits of being associated with high status persons, means that high status philosophers play an outsized role in what we discussion.
Historical Cues. Philosophers are also driven by social issues as they arise in history and culture, and those issues are in many respects random, and generally impossible to predict. Current events doesn’t change physics or biology much at all, but it does change philosophy a lot.
Science Envy. It has been quite common in the history of philosophy for philosophers to take their cues from scientists in how to formulate and address philosophical problems. This means that much of philosophical discussion is affected by scientific progress, and which sciences seem the most sturdy and progressive. But scientific progress is itself hard to predict and often occurs in unexpected paradigm shifts. That means philosophical theories are likely to be blown about by the progress of the sciences.
Popular Disgust. It has also been quite common in the history of philosophy for philosophers to approach the opinions of the masses with disgust (probably also because philosophers want to be high status, and so want to distinguish themselves from the masses, but also because the masses have easily refutable views). So philosophy is often reactive, generating discussions about views common in popular culture in order to distinguish themselves from popular culture.
Follow the Money. Philosophers have, for a very long time, depended on the patronage of non-philosophers, and this, I think, has shaped what philosophers talk about up to today (in many ways, these days our patrons are the general public and our students’ parents).
Unseriousness. For reasons I don’t quite understand, philosophers spend a lot of time dismissing some positions as unserious. This is often due to the fact that philosophers sense that their views are pretty bizarre and so are sensitive to the fact that they need to show that they’re sensible and not sophistical. And this is also in part due to science envy and popular disgust. Views held by scientists and rejected by the people will tend to influence philosophy more than other views. That’s one reason theism is low status in philosophy today. Atheism is common among leading scientists, and theism is common among the masses.
Counterfactual Philosophers. A huge amount of philosophical progress is determined by the personal idiosyncracies of the people who decide to become philosophers. Our field could be quite different if different philosophers, counterfactual philosophers, were part of the field. Have we any doubt philosophy would be different if the leading physicists had become philosophers instead?
Given all these factors, why think philosophy makes progress of any kind? Well, because people put forward inventive theories and other philosophers refute them, so we learn which views are erroneous. And periodically, there’s a new system of thought that organizes information in new and illuminating ways. So we come to know more than we knew before.
So we make philosophical progress, but because the space of concepts and arguments is so big, there is invariably path-dependence and speciation in the direction philosophy takes. But if I’m right, any progressive path is going to be determined by arbitrary factors, so we perhaps can’t be too upset about the particular arbitrary factors that drive us forward unless we think those factors are slowing progress down.