In many ways, ours is an anti-intellectual age. We are less likely to agree with Ruskin defining the greatest artist as he ""who has embodied, in the sum of his Works, the greatest number of the greatest ideas,"" than with Eliot famously praising Henry James for having the sort of mind which ""could not be violated by an idea."" For Professor Boas, ""the history of ideas tells us among other things how we got to think the way we do -- and if that is not of importance, one wonders what is."" This is probably true, but the rationalist bias behind the statement suggests the sensibility of an eighteenth century thinker rather than that of a modern savant. Nowadays people weary of ideas because they've all turned into isms -- Freudianism with its labels, Marxism With its ideology. Professor Boas ""recognizes the real existence of chance and is willing to settle for the probable and not seek the absolutely true,"" but his wise and agreeable study, though engagingly concerned With beliefs, metaphors, personifications, movements, social structures and systems, millenarianism or Manifest Destiny, seems both vaguely libertarian in its assumptions (""the human mind is an active force... and not an inert patient upon which economic, erotic, or even social causes operate"") and rather remote from the irrationalist temper of recent history. Boas is best when dealing directly with the ""problems of intellectual historiography,"" especially the chapter on the subversion of monotheism and its deft conclusion: ""The philosophic transformation of the one God of the Old Testament into a multiplicity of metaphysical gods has had the effect of denying the reality of that which the procedure was supposed to prove."" Elsewhere the erudition exfoliates a bit randomly.