The growing concern throughout the world for the logic, the history, and the sociology of science reveals a comprehensive international movement interested in considering the scientific enterprise in its entirety. The purpose of the International Encyclopedia of Unified Science, as originally conceived by the late Otto Neurath, was to explore in numerous volumes the foundations of various sciences and to aid the integration of scientific knowledge. Circumstances during World War II and the death of Professor Neurath, however, limited the scope of the Encyclopedia. The Foundations of the Unity of Science constitutes the only completed unit of the proposed multi-volume Encyclopedia.

"This book is valuable as expounding in full a theory of meaning that has its roots in the work of Frege and has been of the widest influence. . . . The chief virtue of the book is its systematic character. From Frege to Quine most philosophical logicians have restricted themselves by piecemeal and local assaults on the problems involved. The book is marked by a genial tolerance. Carnap sees himself as proposing conventions rather than asserting truths. However he provides plenty of matter for argument."—Anthony Quinton, Hibbert Journal