The worry that unreflective belief acquisition may be unreliable, after all, applies equally to reflective belief acquisition: it too may be unreliable. To my mind, the plausibility of internalist views about justification is dramatically decreased when one becomes vividly aware of what introspection and reflection actually achieve.
There is a worry that many have expressed that, on the naturalistic way of approaching philosophical questions, philosophy will somehow be co-opted by science. I'm not much worried about this.
No one worries terribly much about who the questions belong to, or whether a given contribution is really philosophy or, instead, properly nothing but science. Perhaps another way to put this is that, although I think that knowledge is a natural kind, I don't think that philosophy is.
