Physical Unknowables

In what follows, a variety of physical unknowables will be discussed. Provable lack of physical omniscience, omnipredictability and omnipotence is derived by reduction to problems that are known to be recursively unsolvable. “Chaotic” symbolic dynamical systems are unstable with respect to variations of initial states. Quantum unknowables include the random occurrence of single events, complementarity, and value indefiniteness. From antiquity onward, various waves of (in)determinism have influenced human thought. Regardless of whether they were shaped by some Zeitgeist, or whether, as Goethe’s Faust puts it, “what you the Spirit of the Ages call, is nothing but the spirit of you all, wherein the Ages are reflected,” their proponents have sometimes vigorously defended their stance in irrational, unscientific, and ideologic ways. Indeed, from an emotional point of view, may it not appear frightening to be “imprisoned” by remorseless, relentless predetermination, even in a dualistic setup (Descartes, 1641); and, equally frightening, to accept that one’s fate depends on total arbitrariness and