Even seasoned relativists can sometimes fail to reach a consensus, a situation that demands a scrutiny of fundamentals. Geared toward readers already acquainted with special relativity, this book transcends the view of theory as a working tool to address potential barriers to a complete understanding. It offers an examination of the natural questions about relativity theory: What is the role of the "observer"--is he to be identified with some frame of reference or is he outside of any frame? What is an "event"? Can the "conventional" element in the "definition" of distant simultaneity be avoided? As this volume's Introduction notes, "Bridgman's profound and far-reaching analysis of space, time, and causality in Sophisticate's Primer is presented on a level that is basic enough to be appreciated by a wide spectrum of readers. It is a fine example of an analysis of foundations tempered by a philosophical view that continues to be relevant--the operational point of view." Unabridged republication of the second edition originally published by Wesleyan University Press, Middletown, Connecticut, 1984. Introduction by Arthur I. Miller. Bibliography. Index.