Oh no not another free will thread.

[Mystic]

That's why we're talking about a being knowing the future, because it's another way of thinking about the same sort of thing.

I like thinking about this stuff with time travel.

In a world with free will, I'm presented with an Apple, a Banana, and a Cucumber.  Larry video tapes me choosing the Banana.  Larry then sends the video tape back through time to himself 3 hours ago and watches it. 

So when the event occurs again, Larry secretly bets George 10 dollars I'll choose the Banana.  But this time I choose the Cucumber.  

Because Larry knowing the outcome of the reality that occurred doesn't negate the possibilities of other realities occurring.

An all knowing being knowing the outcome of the choices we will make doesn't negate our ability to have made other choices.  We just didn't happen to make them.  We determined the all-knowing beings knowledge, rather than the all-knowing beings knowledge determining us.

I don't believe in free will, but that's how I'd deal with this if I did.

The thing is "back through time" would mean, past, present, future is some sort of stream that all exists at once. If this is true, then indeed free-will is impossible per the argument shown. He would have the illusion of free-will, but if the future is discovered, he can't choose otherwise, if it's truly a determined inescapable future.