There exists a great chasm between those,
on one side [hedgehogs], 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, organising principle in terms of which alone all that they are and say has significance” and,
on the other side [foxes], 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 to 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, moving on many levels, seizing upon the essence of a vast variety of experiences and objects for what they are in themselves, without, consciously or unconsciously, seeking to fit them into, or exclude them from, any one unchanging, all-embracing, sometimes self-contradictory and incomplete, at times fanatical, unitary inner vision.
Isaiah Berlin, The Hedgehog and the Fox: An Essay on Tolstoy’s View of History. London, 1953, p. 436-437.