The effort to achieve greater European unity has absorbed the interests and energies of a number of Europeans and Americans since the end of World War II. Edward Heath, who led Britain's earliest attempt to join the European Economic Community, first made this comprehensive statement of the philosophy and purpose behind the movement for European unity in a series of lectures he gave at Harvard University in March 1967. Mr. Heath has updated the lectures in his introduction, although his lucid and intelligent analysis remains extremely far-sighted even in the context of subsequent political changes and events.