It has been a constant intention of the series of AMERICAN UNIVERSITY PUBLICATIONS IN PHILOSOPHY to present to the philosophical reader books which probed the frontiers of contemporary philosophy. That intention remains true of the following volume, which offers an international dialogue regarding the phenomenological program and succeeding movements. Early in this Series we tried, as well, to initiate philosophical discussion across serious boundaries and barriers which have characterized contemporary reflection. That theme also continued in the original essays presented herein. With the publication of this fifth volume in the Series we have crossed something of a minor milestone in our endeavor, and are appreciative of the kind welcome with which we have been received by the readers. We wish to thank sincerely the contributors to this volume for their helpful and willing cooperation. We also wish to thank Ms. Irmgard Scherer for her translation of Professor Apel's paper, as well as Professor Apel himself for reviewing this translation. We are also pleased to thank the Office of the Dean of the College Of Arts And Sciences and especially Dean Betty T. Bennett, for a grant for typing, as well as Ms. Mary H. Wason for her fine typing skills and her kind cooperation.