Determinism holds that all events follow a causal chain, dictated by the laws of physics. If determinism is true (empirical stance), theoretically someone could construct a supercomputer that could process all physical facts about the universe at any given moment, and, via various calculations, essentially “predict the future”. An operator of such a machine could then view this future, which would comprise all future events of the universe. Oddly enough, the operator could then, knowing the future, alter it otherwise. Hence, potential paradox.

Of course, it seems in reality that this paradox is avoided by the introduction of uncertainty via quantum physics. Quantum physics says that nothing is certain, and that the best we can really do is know the probability that one event will occur over another.

Let’s simplify everything now with a brief thought experiment. An operator locks himself in a small room (assume closed system), and enters every physical facts of that “system”, down to each atom, into his personal supercomputer. There is nothing in the room except the operator, his computer, and a light switch. 5 minutes after running the calculations the operator plans to consider turning on the light. After running the calculations, the computer outputs all future events of the closed system, including that the man will flip the light switch in 5 minutes. The man then chooses not to do so.

Paradox? It seems quantum physics wouldn’t allow us to ultimately predict with certainty the future, so maybe not. Even if the conclusion was that 99.999999% likelihood the operator would flip the switch, it avoids the potential paradox (there is no contradiction).

What if the operator decided to always do the opposite of the prediction? In this case, the prediction would never be correct, even though it has taken into consideration every physical fact of the system. How is this possible?