"D'Alembert" is a popular science book written in Ukrainian by the author Bertrand Joseph. In this work, the author reveals the life path and scientific achievements of the outstanding French mathematician, philosopher and encyclopedist Jean Le Ron D'Alembert. The book tells about D'Alembert's contribution to the development of mathematics, physics, philosophy and other scientific fields, and also highlights his important ideas and influence on the development of world science. This book will be a useful source of information for anyone interested in the history of science and the figure of outstanding scientists.