Good,” said the First Speaker. “And tell me, what do you think of all this. A finished work of art, is it not?”“Definitely!”“Wrong! It is not.” This, with sharpness. “It is the first lesson you must unlearn. The Seldon Plan is neither complete nor correct. Instead, it is merely the best that could be done at the time. Over a dozen generations of men have pored over these equations, worked at them, taken them apart to the last decimal place, and put them together again. They’ve done more than that. They’ve watched nearly four hundred years pass and against the predictions and equations, they’ve checked reality, and they have learned.
Isaac Asimov, Second Foundation
psychohistory, science-fiction