Each situation requires a balancing derived from judgment and arising from experience, skills acquired by learning from the past and training for the future.
Theory reduces history's complexity to teachable moments.... Instead theory functions, with respect to the past, as Clausewitz's coups de'oeil do in the present: it extracts lessons from infinity variety. It sketches, informed by what you need to know, without trying to tell you too much. For in classrooms as on battlefields, you don't have unlimited time to listen. Theory, then, serves practice. And when practice corrects theory - when it removes theorists' horse blinders - it returns the favor, preventing stumbles off cliffs, into swamps, and toward Moscow.
- John Lewis Gaddis On Grand Strategy discussing Tolstoy and Clausewitz as the grandest strategists