The Yogi and the Commissar (1945) is a collection of essays of Arthur Koestler, divided in three parts: Meanderings, Exhortations and Explorations. In the first two parts he has collected essays written from 1942 to 1945 and the third part was written especially for this book.

In the title essay, Koestler proposes a continuum of philosophies for achieving "heaven on earth", from the Commissar at the materialist, scientific end of the spectrum, to the Yogi at the spiritual, metaphysical end. The Commissar wants to change society using any means necessary, while the Yogi wants to change the individual, with an emphasis on ethical purity instead of on results.

(Source: Wikipedia)