The book offers a detailed analysis of the philosophical and intellectual shifts that led to the conception of an infinite universe.

This collection of six essays centers on Professor Koyre's great theme: the relative importance of metaphysics and observation, with controlled experiment a kind of marriage between the two.

Seven essays which illustrate by means of conceptual analysis the way in which fundamental scientific ideas are at the same time related to the main currents of philosophical thought and yet determined by empirical controls.