There is a line among the fragments of the Greek poet Archilochus which says: \"The fox knows many things, but the hedgehog knows one big thing\". Scholars have differed about the correct interpretation of these dark words, which may mean no more than that the fox, for all his cunning, is defeated by the hedgehog's one defence. But, taken figuratively, the words can be made to yield a sense in which they mark one of the deepest differences which divide writers and thinkers, and, it may be, human beings in general.For there exists a great chasm between those, on one side, who relate everything to a single central vision,one system less or more coherent or articulate; in terms of which they understand, think and feel-a single,universal, organizing principle in terms of which alone all that they are and say has significance and, on the other side, those who pursue many ends, often unrelated and even contradictory,connected, if at all, only in some de facto way, for some psychological or physiological cause, related by no moral or aesthetic principle; these last lead lives, perform acts, and entertain ideas that are centrifugal rather than centripetal, their thought is scattered or diffused,