Tom Lehrer has a song which begins "Whatever Happened to Hubert?". I should like to change that to "whatever happened to empirical knowledge?". By empirical knowledge I mean, to borrow phrases of David Hume, knowledge of matters of fact based on experience. Hume, as you know, declared that all knowledge of matters of fact is based on experience, and I am inclined to believe that almost all philosophers hold the converse, namely that all knowledge based on experience is knowledge of matters of fact. Yet a perusal of the recent literature leads one to wonder whether either of these generalizations can be maintained, and whether there is indeed any interesting empirical knowledge. Where by interesting empirical knowledge I mean what Hume called knowledge of matters of fact "beyond the present testimony of our senses, or the records of our memory".¹ Let me hasten to assure you, however, that despite these references to Hume my concern is not with scepticism.