Daniel Kuehn claims that "a priorism is a bad way of understanding the world."
Well, that is true to the same extent that empiricism is a bad way of understanding the world. For instance, it is a well-known finding in the philosophy of science that, given an empirically adequate theory of some phenomenon which theory we accept, it is trivial to generate an infinite number of other equally empirically adequate theories. (For instance, just keep adding more variables that exactly balance each other out in getting the observed result.) Certainly we cannot have empirical grounds for rejecting such theories: they are, after all, created to be empirically equivalent to the theory we accept. Therefore, our grounds must be "a priori." (I'm not sure that is the best way to put that, but it will do for this debate.) Or consider, for instance, how Einstein decided that one cannot catch up with a light beam: it certainly was not because he kept experimenting with ways to do so and found they all failed!
Good scientific method requires a delicate balance of empirical and rational judgment. How do you get that balance right? The same way you get to Carnegie Hall.