1978 Reprint Hardback Two Volume Set. Published by Harvester Press with George Allen & Unwin Ltd.  Vol. I: 654pp; Vol. II: 532pp. Blue cloth with clear gilt titling to the spines.  Some staining to the front cover of vol. one. Slight wear to top and bottom of spine.

Written in 1939, includes the movement of reflection, invention, truth, and the goal of thought.