Hmm, this is a good question. After spending some time thinking about this, I think the problem I have in trying to separate "history of philosophy" from "philosophy" is that such an enterprise almost appears antithetical to the goal(s) of philosophy. Philosophy seems meant not to be useful or practical, but intended to ask the right sorts of questions, think about things one abstraction deeper/more meta, and question things others don't question. As such, studying the history of philosophy is philosophy--and vice versa--insofar as the goal of philosophy is not to positively answer* the right questions but to think philosophically and ask those questions in the first place. So, learning why Aristotle's ideas on physics are wrong is simply not the sort of thing with which philosophy would concern itself--for better or for worse.
*Thinking about it some more, I just realized that I may be conceiving of the goal(s) of philosophy as something different than what most of the posters here do. I get the sense that lukeprog (and others here) wants philosophy to provide answers to the deep questions, or at least attempt to do so. The problem is philosophy is not about that; maybe it should be, but then I'd argue that such a field is precisely what science is, with philosophy as almost a check/balance (making sure that the right questions are still being asked, assumptions questioned, etc.).
Philosophy seems meant not to be useful or practical, but intended to ask the right sorts of questions, think about things one abstraction deeper/more meta, and question things others don't question.
How is asking "the right sorts of questions" not "useful or practical"? To "question things others don't question" is what scientists do. Examples: Why do things fall down when let go? (physics) Why do children tend to look like their parents? (genetics) Why does a candle burn? (chemistry)
What are the questions "others take...
Part of the sequence: Rationality and Philosophy
Bertrand Russell
I've complained before that philosophy is a diseased discipline which spends far too much of its time debating definitions, ignoring relevant scientific results, and endlessly re-interpreting old dead guys who didn't know the slightest bit of 20th century science. Is that still the case?
You bet. There's some good philosophy out there, but much of it is bad enough to make CMU philosopher Clark Glymour suggest that on tight university budgets, philosophy departments could be defunded unless their work is useful to (cited by) scientists and engineers — just as his own work on causal Bayes nets is now widely used in artificial intelligence and other fields.
How did philosophy get this way? Russell's hypothesis is not too shabby. Check the syllabi of the undergraduate "intro to philosophy" classes at the world's top 5 U.S. philosophy departments — NYU, Rutgers, Princeton, Michigan Ann Arbor, and Harvard — and you'll find that they spend a lot of time with (1) old dead guys who were wrong about almost everything because they knew nothing of modern logic, probability theory, or science, and with (2) 20th century philosophers who were way too enamored with cogsci-ignorant armchair philosophy. (I say more about the reasons for philosophy's degenerate state here.)
As the CEO of a philosophy/math/compsci research institute, I think many philosophical problems are important. But the field of philosophy doesn't seem to be very good at answering them. What can we do?
Why, come up with better philosophical methods, of course!
Scientific methods have improved over time, and so can philosophical methods. Here is the first of my recommendations...
More Pearl and Kahneman, less Plato and Kant
Philosophical training should begin with the latest and greatest formal methods ("Pearl" for the probabilistic graphical models made famous in Pearl 1988), and the latest and greatest science ("Kahneman" for the science of human reasoning reviewed in Kahneman 2011). Beginning with Plato and Kant (and company), as most universities do today, both (1) filters for inexact thinkers, as Russell suggested, and (2) teaches people to have too much respect for failed philosophical methods that are out of touch with 20th century breakthroughs in math and science.
So, I recommend we teach young philosophy students:
(In other words: train philosophy students like they do at CMU, but even "more so.")
So, my own "intro to philosophy" mega-course might be guided by the following core readings:
(There are many prerequisites to these, of course. I think philosophy should be a Highly Advanced subject of study that requires lots of prior training in maths and the sciences, like string theory but hopefully more productive.)
Once students are equipped with some of the latest math and science, then let them tackle The Big Questions. I bet they'd get farther than those raised on Plato and Kant instead.
You might also let them read 20th century analytic philosophy at that point — hopefully their training will have inoculated them from picking up bad thinking habits.
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