The average detective story is probably no worse than the...

The average detective story is probably no worse than the average novel, but you never see the average novel. It doesn't get published. The average -- or only slightly above average -- detective story does.... Whereas the good novel is not at all the same kind of book as the bad novel. It is about entirely different things. But the good detective story and the bad detective story are about exactly the same things, and they are about them in very much the same way.