Fyerabend is the top dog right now I wouldn't recommend investing too much in him, he basically thinks there is no demarcation and Voodoo and Einstein are equally valid.

I accept Quine who I admit isn't much better, he thinks it's all about creating a coherent world view. I think he's onto something but he's missing truth which I think is a problem - we want to think science gives us truths about the world, or at least we want a way to get to truth.

There's another view that says science starts with a set of untested assumptions which I haven't gotten around to reading much about