I just finished up my philosophy undergraduate degree here at the University of Wisconsin in Madison, and I thought the program was incredible (well, the parts on social/political/ethical/economic philosophy were; I don't love the M&E stuff, but not due to any failing of the program, I don't think). I can't really speak for other programs, but I'd definitely recommend this one. I got to take an economic philosophy course from one of the more important figures in the field (Dr. Dan Hausman), and a philosophy of the social sciences course with him as well; I took political philosophy with a libertarian professor (Dr. Lester Hunt), and got to read and examine Locke, Nozick, Otsuka, and Cohen for class credit; I got to write my thesis on a libertarian approach to the ethics of climate change with an egalitarian professor (Dr. Harry Brighouse), who was absolutely fantastic to work with because of just how differently we view things; I got to go to free philosophy conferences and lectures, including a brief opportunity to debate with Dr. David Friedman when he came to campus this spring...I could go on, but the point is I had an awesome experience here, and all I had to do was pay up, show up, and work hard.
I guess it's possible that I could have done it on my own. Maybe. But it was so much easier to do it here. It's like training for the Olympics. Technically, anything you can get from a coach, you can either figure out for yourself or hire someone to do for way less money. But good luck making that work. I think if you want to study philosophy -- and I mean really study it, not just memorize the position of one school of thought and think it's the complete gospel truth, no matter what ridiculous positions it commits you to -- there really is no feasible alternative to getting at least some help in an academic setting. That doesn't mean specifically studying philosophy; Geoffery, for example, is studying political science. But it's not a coincidence that most important modern philosophers work in academia, or at least have formal educations in philosophy or a related field.
That being said, if you could see yourself being happy doing anything else besides being a professional philosopher, I'd say do that instead. You pretty much have to be crazy to want to pursue a career in philosophy. But if you are crazy, then get yourself into school as quickly as possible.
If you're trying to decide where to go, I'd recommend first taking a look at the Philosophical Gourmet, especially the sections where rankings are offered for individual areas of philosophy. Rankings are inherently shaky, but they're a good starting point. When you have an idea of some places you might like to go, check out the publications for the faculties. If you can't find professors in a department that are looking into subjects that you find interesting, you might want to take that into account (though not too much; you'll just be an undergraduate, so most of the better professors' level of knowledge will be sufficient for your purposes, even if they don't specifically focus on the exact area that you're interested in). Also make sure you like the city, the campus, and the rest of the school. You'll be spending four years there; don't go somewhere where you'll be miserable. Hopefully that helps a little bit; if you have any questions, feel free to ask!
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