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.