Via Daily Nous, I came across this piece by Graham Priest, on the value of the history of philosophy:
If you go into a mathematics class of any university, it’s unlikely that you will find students reading Euclid. If you go into any physics class, it’s unlikely you’ll find students reading Newton. If you go into any economics class, you probably won’t find students reading Keynes. But if you go a philosophy class, it is not unusual to find students reading Plato, Kant, or Wittgenstein. Why? Cynics might say that all this shows is that there is no progress in philosophy. We are still thrashing around in the same morass that we have been thrashing around in for over 2,000 years. No one who understands the situation would be of this view, however.
So why are we still reading the great dead philosophers? Part of the answer is that the history of philosophy is interesting in its own right. It is fascinating, for example, to see how the early Christian philosophers molded the ideas of Plato and Aristotle to the service of their new religion. But that is equally true of the history of mathematics, physics, and economics. There has to be more to it than that—and of course there is.
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Graham’s answer, it seems to me, gets at part of the truth, but does not capture it all. The rest of his blog post focuses on different ways in which paraconsistent logic (or mathematical ideas more generally) can be used to take some wacky idea to be found in the work of the great dead philosophers and make it consistent, thereby opening up new vistas for philosophical theory. (This is a variant on the view that the value of the history of philosophy derives from what it promises to deliver in the way of present-day philosophical enlightenment.) The problem with this as a general account of the value of the history of philosophy is that it is possible to apply paraconsistent logic (and other mathematical tools) to practically anything you choose, whether it be an idea found in Plato or an idea found in Hawking. Mathematical tools at the level of paraconsistent logic are just SO powerful that everything to which they are applied pales in significance relatively speaking.
Here’s a connected point, using an example of Graham’s own. Suppose I think that the Third Man Argument shows that what unifies a proposition cannot be part of the proposition on pain of vicious infinite regress. Now Graham comes along and claims that what unifies a proposition can be identified, without inconsistency (in paraconsistent logic), with each of the proposition’s parts. Well, that’s certainly news. Good for Graham. He’s opened up a new theory of propositional unity. But notice that he’s really left the original TMA in the dust. The TMA is valuable for him only inasmuch as it functions as a (totally contingent) jumping off point. The TMA reasoning itself is left in the dust, because one of its premises has been rejected. Notice how different this is from the view that we have something to *learn* from the TMA itself. On this view, the regress really is vicious, and the conclusion stands. What we learn from this is that the form or structure of a proposition is not one of its parts. You can think of this as the beginning of generative syntax, if you like. As such, it is a profound result. Now that’s really getting bang for the buck from the history of philosophy!
(Note: Graham says that you won’t find today’s physics students reading Newton and you won’t find today’s economics students reading Keynes. Well, that’s not quite accurate. First, physics students do study Newtonian mechanics, even if they don’t *read* the *Principia* itself. They learn the ideas, even if they don’t learn the way in which those ideas were presented. That’s certainly something. Second, if you read Krugman and other “demand-side” economists these days, you will notice that they consistently refer back to Keynes, often quoting directly from Keynes himself. You will also find syllabi on the internet, for example this one, that start with a close reading of Keynes and then consider sophisticated extensions of his theory: http://cas.umkc.edu/econ/economics/faculty/wray/601wray/syllabus.htm.)
So I don’t think that the central value of the history of philosophy has to do with its ability to serve as a contingent source of new philosophical ideas through the application of powerful mathematical tools. But also, ethics and political philosophy aside (here I really do think that the entire history of philosophy offers us central ideas that still animate these disciplines, with arguments that still really matter for our purposes), I don’t think that the central value of the history of philosophy has to do with the fact that its *content* continues to enlighten us now. Although there are contemporary hylomorphists, my view is that that ship sailed a long time ago. Syllogistic has been replaced by something better, and anything built on it (medieval logic, Kant’s theory of judgment) just won’t stand the test of time. None of those wonderful arguments (in Aquinas, Descartes, Locke, Leibniz, Berkeley, and so on) for the existence of God works. Locke’s theory of knowledge, fascinating as it is, is just false. And on and on. No: leaving aside the appeal of studying it for its own sake (this is true of almost anything interesting), the history of metaphysics and epistemology (broadly understood) is valuable mostly because the great dead philosophers serve as shining examples of how to do philosophy, how to think philosophically, how to set up a philosophical problem and solve it using a new set of tools, how to probe a philosophical system and find its central weaknesses, and so on. To understand how Plato himself gets out of the Third Man Argument in the *Parmenides*, to understand how all the different moving parts of Kant’s/Aristotle’s philosophical system hang together, to watch the desperate wriggling of a cornered Descartes caught on Elisabeth’s devastating hook, to watch Cavendish make room in logical space for thinking, intelligent matter in the face of opposition that treats the view as borderline incoherent, to rationally reconstruct the reasoning *more geometrico* in Spinoza’s *Ethics* (just to take a few examples), is to become a better philosopher. By contrast, I find that the *range* of philosophical options and the *range* of philosophical moves somewhat more restricted in contemporary philosophy, at least as currently practised. If you want to learn what it looks like to really think outside the box (in addition to learning what it’s like to add an epicycle to an epicycle to an epicycle, or what it’s like to object to an epicycle to an objection to an epicycle), study the history of philosophy. This will serve you well when you try to come up with your own original and deep philosophical ideas.
I am not sure he provides an answer, he just says there is more to it. There are different sorts of intellectual issues. Some are problems to be solved: most straightforward mathematical questions are like this. You work them out and then move on to something else. Likewise technological advancements in science, a new and more effective solution replaces a older less effective one. In such cases history is merely contingent. It may be interesting and incidentally helpful but it is not an integral and necessary part of the pursuit. Other types of issues are mysteries to be pondered. Why does something exist rather than nothing? How should I live? Etc. The answers to such questions are not determined once and for all, a new response may nuance or deepen a prior one and competing views are to be expected. Philosophical questions involve a mixture of both problem and mystery to be sure, but the mystery predominates. Expecting a new philosophy to definitively replace a traditional one would be like finding it odd that anyone would listen to Mozart after hearing Beethoven. This isn’t to say that anything goes, but that in such cases the truth is disclosed progressively and incompletely.