This series provides a forum for the critical review of enduring issues concerning ethics and society. The text of the debate between Herbert Marcuse and Sir Karl Popper which follows in this volume raises many important issues. The crucial issues between the two participants are (1) their anthropological-axiological positions with respect to the nature of man, society, and the practical functions of democracy as a mode of self-government; (2) the conceptions of science and of philosophy which lie behind each thinker’s claims with respect to these; and (3) their respective conceptions of the means required and feasible for attaining their respective social goals. The remarks which follow will attempt to focus upon, and deal critically with, the problems implicit in these three areas.