 I can say in all seriousness that twenty years ago I regarded Wilson’s Statement and Inference as the philosophical book of the century, and Prichard’s lectures on perception and on moral philosophy, which I attended with excitement, as veritable models of exposition and analysis. I may add that while my philosophical ideas have undergone considerable changes since 1935, I still think that some of the best philosophical thinking of the past hundred years was done by these two men. (Sellars 1957, 458).