"Pure mathematics, being mere tautology, and pure physics, being mere fact, could not have engendered them; for creatures to live, must sense the useful and the good; and engines to run must have energy available as work : and both, to endure, must regulate themselves. So it is to Thermodynamics and to its brother Σp log p, called Information theory, that we look for the distinctions between work and energy and between signal and noise."