In a discussion thread in an unlikely place, I encountered the absurd claim that Sir Peter Strawson was a greater philosopher than David Lewis. This got me to thinking about the game of rating philosophers in general, and as I've been getting some work done on the dissertation recently, I have a highly accurate, entirely objective standard to apply. Specifically, I can evaluate them on the basis of how useful they are to me in my efforts to expand and improve my dissertation draft.
According to that standard, William Lycan is underrated. His notion of a two-level fallacy in the philosophy of mind is highly fruitful. Jerry Fodor is overrated. He says nothing right that isn't better said by someone else, and nothing wrong which is not either better said by someone else or too silly to be worth responding to. Donald Davidson's reputation is probably about where it belongs.