Carl G. Hempel (1905-1997) was one of the preeminent figures in the philosophical movement of logical empiricism. The essays in this collection come from the early and late periods of Hempel's career. Most of these essays are hard to track down and four of them are appearing in English for the first time. Cumulatively they offer a fresh perspective on Hempel's intellectual development and on the rise and demise of logical empiricism. Richard Jeffrey has prepared the collection for publication, and has supplied introductory surveys to the essays as well as a brief biographical sketch of Hempel.