THE SCALE OF THE UNIVERSE DEBATE IN 1996

On April 21, 1996, Sidney van den Bergh and Gustav Tammann engaged in a public debate titled ''The Scale of the Universe.'' The arguments th ey presented focused on recently determined and still controversial va lues of the Hubble Constant. The program was moderated by John Bahcall , with lectures on the background and history behind humanity's quest for the scale of the Universe given by Owen Gingerich and Virginia Tri mble. These introductory lectures along with the arguments presented b y the 1996 debaters are recreated in the following papers. This debate was of the same title and held in the same auditorium as the ''Great Debate'' between Heber Curtis and Harlow Shapley in 1920. Here we disc uss some of the issues surrounding the organization and inspiration fo r the 1996 debate, Like the 1920 debate, the 1996 debate was not inten ded to resolve a disagreement instantly. Instead it is hoped that this debate and the written contributions will stand as educational tools, summarizing the arguments behind today's Hubble Constant controversy, and will help provide a framework for evaluating progress in this fie ld as the century which saw its creation draws to a close. Together wi th last year's debate, ''The Distance Scale to Gamma Ray Bursts'' (Nem iroff, R. J. 1995, PASP, 107, 1131), these papers may also provide a c lue as to how scientists think.