With one exception, all of the papers in this volume were originally presented at a conference held in April, 1978, at The Ohio State University. The excep tion is the paper by Wilfrid Sellars, which is a revised version of a paper he originally published in the Journal of Philosophy, 1973. However, the present version of Sellars' paper is so thoroughly changed from its original, that it is now virtually a new paper. None of the other nine papers has been published previously. The bibliography, prepared by Nancy Kelsik, is very extensive and it is tempting to think that it is complete. But I...