In Vienna in the 1920s a group of brilliant philosophers, mathematicians, and scientists – led by figures such as Moritz Schlick, Otto Neurath, Rudolf Carnap, and Hans Hahn – gathered to discuss the foundations of science and mathematics. Known as the Vienna Circle, they proposed to practice philosophy in continuity with science; their movement became known as Logical Empiricism. In this highly engaging book, Sahotra Sarkar tells the story of one hundred years of Logical Empiricism, from its beginnings in 1924 to its legacy today. He explains how its ideas, influenced by revolutionary theories of space, time, and causality of that time, led to a quest for a unified theory of science. He shows how their commitment to logic and objectivity provided a powerful political antidote to Nazi racism and obscurantism. He charts the decline of the movement after many members, who had fled to the United States during World War Two, were presumed to have communist sympathies and subjected to surveillance and harrassment. He argues that the ideas of the movement continue to be relevant today. A superb evocation of one of the most important intellectual movements of the twentieth century, The Vienna Circle: The Story of Logical Empiricism will be of great value to anyone interested in philosophy, history, and the history of science.