MindAndPhilosophy wrote:I've been thinking about the free will problem for some time and I'd want to ask you something: do you think it is possible to prove that determinism is false?
Sure:
1) at time zero I am undecided about which of two options to enact at time three
2) if determinism is true, then at time zero there is a fact about which option I will enact at time three
3) at time one I state that I will enact option
A only if a certain as yet unknown condition obtains at time two, and option
B if that condition doesn't obtain
4) for the unknown condition, I can choose something causally isolated, for example an astronomical observation, and such that the probability of it matching my choice is one half
5) at time two I make the observation and at time three I enact the stated option according to whether or not the condition is met
6) if I can enact the stated option, then the probability of determinism being the case is one half. If I can behave like this consistently for an arbitrarily long series of consecutive tests, then the probability of determinism being true is vanishingly small
7) but if I can't behave like this, as making the selection is equivalent to making an observation, the probability of my observations matching an external world becomes vanishingly small
8) if the probability of my observations matching an external world is vanishingly small, then, in a correspondence sense, the probability of any argument for determinism having true premises is vanishingly small
9) so, in either case one cannot rationally accept the truth of determinism
10) therefore, the only rational stance is that determinism must be held to be false.