How Free Will and Omniscience Works

[Jackalope]

OK, in the event where he votes Democrat without the coercion of the device, how is it not a free choice?

It depends on what you mean by "free choice" (and/or "free will").

The question of free will is one that's been debated since antiquity, and there is no consensus as to what "free will" is. My personal view is that if free will exists (and I am undecided if it does), then free will is incompatible with determinism (and therefore incompatible with precognition).

If you take the compatibilist viewpoint, and see free will as the freedom to act without coercion or restraint but not necessarily without pre-determination, your only problem is that you've redefined "choice" to mean something other what it means. Either that, or you've redefined what it means to be omniscient/precognitive.

Consider standard definitions of "choice", "omniscience", "precognition" and "knowledge":

• Choice: An act of selecting or making a decision when faced with two or more possibilities
  
• Omniscience: Knowing everything
  
• Precognition: The ability to know future events.
  
• Knowledge: Justified true belief.
  

When constrained by these definitions, there is no choice. If before you act, an omniscient/precognitive entity knows that you will choose A and not B, B is not a possibility at all. You cannot choose B when you invoke omniscience/precognition that knows otherwise - not without invalidating what it means to be omniscient/precognitive. If you could choose B, the entity's "precognition" that you would choose A would not be true, or known (things that are false are tautologically not known), and the precognition is not precognition at all (because to be precognition, the events forseen must necessarily be true).

There is no selection, no decision, and there is in fact only one option, and no choice is possible. This is true even if the omniscient/precognitive entity does not force your hand. There is no coercion, but your choice is restrained by the precognitive's future knowledge of your action.

You therefore have no capacity to act freely when you invoke a precognitive omniscient entity who knows your future actions, and your perception of free will in that case is illusory.

Now, you can certainly do as the compatibilists have done and redefine away the problem, but that strikes me as somewhat disingenuous and ad hoc. However, that is what you'd need to do to retain both free will and precognitive omniscience. You can "solve" any dilemma/paradox by redefining the terms - but is that really a solution?

I'll close by saying that an atheist who rejects the compatibilist view doesn't seem likely to find such an argument persuasive.