First off; i cannot find a suitable place for this post, as there is no philosophy dept., but as it involves physics, I decided to post it here. If that is wrong, then I apologize, but implore the mods to create a a philosophy dept.
Ok, so the thought experiment is as such;
If we state that the brain is a complex of natural chemicals, tissues, and all kinds of natural things, which are therefore all subject to natural laws of physics, like causality, then free will is a false notion, as any resulting thought that the brain produces is a mere consequence of those earlier, chemical/physical causes (I for one think this is true).
H.G. Frankfurt had a thought-experiment, which revolved around the idea of an all knowing entity "LaPlace's Demon", that is aware of every physical partical in the universe and also of every physical force/laws To which these particles are subject, and is therefore able to predict any situation of a future point in time (and reconstruct any situation of an earlier point in time).
< metaphore: if you hold up and fill a transparant cylinder with a million marbles and from the bottom end of the cylinder push an object into the mass of marbles, you make every marble in the cylinder move as a consequence. The demon would be able to monitor every marble and predict how much each would move if you push the object into the mass, all because of its awareness of the implications of causality. >
Now let us say that our beloved Randall Munroe has just now built a computer which does just that, and it shows him that after x seconds, he will raise his right hand.
Randall, now having seen that the raising of his right hand is a logical, causally founded consequence, decides to mess with the computer by raising his left hand instead.
However; the computer was aware of every physical process in the universe, and therefore also of the results that Ranall's brain would produce after seeing himself raise his right hand in the future. It would have predicted that Randall would see himself and therefore would in fact raise his left hand, and therefore show Randall that because he would raise his right hand, but saw himself in a prediction, he will raise his left hand after x seconds instead.
But Randall, now having seen that he won't raise his right hand, but his left, decides to raise his right foot.
And so on, ad infinitum.
Does this prove that causality, like the cake, is a lie?
Or does this prove that free will is a cakely lie?
Or does this only prove that causality and free will don't go hand in hand? (a.k.a. 'incompatibilism')
Or does this prove that Causality and free will DO go hand in hand? (a.k.a. 'Compatibilism')
I am very curious as to what you guys can make of this, for with each interesting post on this forum, you seem to generate a magnificent amount of perspective.