Originally Posted by IbnAbdulHakim
Well, big question. I only have time for a short answer, unfortunately, but here goes:
Academic philosophy can be said to provide a testing ground for ideas. Biology, Chemistry, Physics, Psychology, Sociology, Theology, Linguistics, Mathematics and just about any other discipline you could name, were all, at different times, branches of philosophy. Indeed, science used to be known as 'natural philosophy'. Once people take a particular approach in a field of potential knowledge, and they begin to find reliable and repeatable answers for philosophical problems, a new science is born. These new sciences are some of what we can thank philosophy for.
Perhaps the most immediate use of philosophy for a student is as a form of mental training. People who have studied philosophy should be better than most in spotting flawed reasoning, and in solving complex problems that require extensive conceptual thought. They are also less likely than others to be tricked into believing things that are unreasonable.
There are other benefits, too, but those (it seems to me) are the main ones.