The fox knows many things, but the hedgehog knows one big thing.
This fragment of verse by the ancient Greek poet Archilochus serves as an illuminating metaphor the philosopher and intellectual historian Sir Isaiah Berlin (1909-1997) employed in his essay on Tolstoy. (The essay is included in his book "Russian thinkers")
Basically, human beings are categorized as either "hedgehogs" or "foxes". Hedgehogs' lives are embodiment of a single, central vision of reality according to which they "feel", breathe, experience and think - "system addicts", in short. Examples include Plato, Dante, Proust and Nietzsche. Foxes live centrifugal than centripetal lives, pursuing many divergent ends and, generally, possess a sense of reality that prevents them from formulating a definite grand system of "everything", simply because they "know" that life is too complex to be squeezed into any Procrustean unitary scheme. Montaigne, Balzac, Goethe and Shakespeare are, in various degrees, foxes.
Arvan Harvat personal correspondence, June 2004
For Berlin, the age of Enlightenment, for all its many virtues, is the age of hedgehogs, because of its view that, as he put it (in his essay on "The Divorce between the Sciences and the Humanities", 1974, p. 326), "every genuine question has one true answer…" – true for everyone, in every place, at every time; that the process leading to this truth is publicly accessible; and that genuinely true answers do not contradict each other, resulting in a seamless web which holds everything together. He, himself, preferred a more liberal, pluralistic (and, for that matter, Romantic) stance, which abjures the quest for a grand synthesis and asserts instead that, in the clash of ideas, it does not have to be the case that one idea is true and the other is false.
John F. Kihlstrom
Princeton professor Marvin Bressler pointed out the power of the hedgehog during one of our long conversations: "You want to know what separates those who make the biggest impact from all the others who are just as smart? They're hedgehogs." Freud and the unconscious, Darwin and natural selection, Marx and class struggle, Einstein and relativity, Adam Smith and division of labor—they were all hedgehogs. They took a complex world and simplified it. "Those who leave the biggest footprints," said Bressler, "have thousands calling after them, 'Good idea, but you went too far!' "
Conversation between Jim Collins and Marvin Bressler, October 2000.
Those who built the good-to-great companies were, to one degree or another, hedgehogs. They used their hedgehog nature to drive toward what we came to call a Hedgehog Concept for their companies. Those who led the comparison companies tended to be foxes, never gaining the clarifying advantage of a Hedgehog Concept, being instead scattered, diffused, and inconsistent.
Contrary to popular belief, you can major in chemistry and be a fox. Scientists are not all hedgehogs, not even close. Or, you can major in English and be a hedgehog. Being a hedgehog or being a fox is more about attitude and perspective than what academic subjects one pursues. Are you passionate to know? Do you love to learn? Do you see the world from multiple perspectives? Do you want to develop all of your abilities? If your answer is yes, you are probably more like the fox than the hedgehog.
Hobart and William Smith Colleges
Berlin, Sir Isaiah (1953), The Hedgehog and the Fox, New York, Simon & Schuster
The Hedgehog and the Fox - Isaiah Berlin - extract of the original essay
Foxes and Hedgehogs and Hypnosis, Oh My! - John F. Kihlstrom (University of California, Berkeley) - provides a good summary/description, then goes on to suggest that this tension between pluralism (foxes) and monism (hedgehogs) is also characteristic of hypnosis.
The Hedgehog Concept - by Jim Collins - argues that being a hedgehog is the way to go in business.
Hobart and William Smith Colleges :: The Fox and the Hedgehog - includes online Fox quizz