This collection of 12 essays published originally in 1991 is devoted to the general question of science and its relation to, and interaction with, philosophy in the Greek world during the fifth and fourth centuries BC. Thus, the papers address issues concerning the origins and explanatory structure of science, as well as problems peculiar to the mathematical sciences (arithmetic, geometry, harmonics, astronomy) and to natural history and medicine. The contributors include: Andrew D. Barker, J. L. Berggren, Alan C. Bowen, David H. Fowler, Charles H. Kahn, Wilbur R. Knorr, James G. Lennox, G. E. R. Lloyd, Alexander P. D. Mourelatos, Ian Mueller, Joseph Owens, and Robert G. Turnbull.