James Clerk Maxwell Quote
As long as we have to deal with only two molecules, and have all the data given us, we can calculate the result of their encounter; but when we have to deal with millions of molecules, each of which has millions of encounters in a second, the complexity of the problem seems to shut out all hope of a legitimate solution.
In: W.D. Niven (ed.), The Scientific Papers of James Clerk Maxwell (Volume 2)