It is so often said that an understanding of the present relies upon an understanding of the past; in the present age the truth of this is perhaps less patent than formerly. Never before has the world been so divided by conflicting ideologies, never has so much depended upon the finding, not, perhaps, of a reconciliation of the ideologies, but of a means of coexistence. The very continuation of the human race would seem to hang upon a solution of this problem. Through all these lectures runs a single thread, the inevitability of the freedom of man, even if that freedom is liberty for self-destruction. All history has shown that domination of man by man must in the end bring revolt, passive or active, when the right of the individual or the group triumphs over suppression . . . The past may no longer be a certain guide to the future; let us hope that in this one respect history will be the signpost, and that intolerance and exploitation and inhumanity of man to man may some day vanish from the earth. --Kwame Nkrumah, from the Foreword