Someone on reddit made the following argument to me about why physicalism (= the claim that the laws of physics are causally closed) is not true (paraphrased). (I’m posting this as a fun logic puzzle; I know the solution.)
Take a person in a room. Suppose the room is sufficiently isolated to be modeled as independent from the rest of the universe. The person is about to write either “0” or “1“ on a piece of paper. But first, she runs a computer simulation that perfectly simulates the entire room down to every atom. (Has to be possible if physicalism is true! All is atoms!) This simulation will compute absolutely everything about the future of the room, including what the person writes down. It then outputs just this (i.e., either “1” or “0”) to the person. The person sees the answer and writes down the opposite on the paper. This shows that the program doesn’t work, which means such a program is impossible, which means physicalism is false.
I imagine a lot of people reading this will spot the flaw immediately, but if you don’t, care to figure it out?
Someone on reddit made the following argument to me about why physicalism (= the claim that the laws of physics are causally closed) is not true (paraphrased). (I’m posting this as a fun logic puzzle; I know the solution.)
I imagine a lot of people reading this will spot the flaw immediately, but if you don’t, care to figure it out?
A machine that tries to answer a question by first simulating (completely faithfully) how it would answer that question will never terminate.