He was a French philosopher and writer, authoring 23 books and countless smaller works. He initially intended to pursue a career in engineering, but after three years in the trenches of the First World War, he changed his sights to philosophy, eventually moving to Paris, where he obtained a doctorate from the Sorbonne. At the Sorbonne, he occupied the chair of history and philosophy of science from 1940 to 1955. His interests included the philosophy of science, the epistemology of knowledge, particularly the dangers of a priori thinking and questions of objectivity and experimental evidence and the phenomena of consciousness.