The top argument of youtube atheists like Thunderf00t against an omniscient God is the existence of Free Will.
The youtube atheists are a wholesale disappointment in the philosophy department though as they actively refuse to acquire knowledge of the centuries of philosophical thought about this apparent conundrum. None of them ever asks himself, hey, maybe some CHRISTIAN or JEWISH thinker of millenia past has already stumbled across this?
Hume is one; Kant obviously another one, Schopenhauer, Nietzsche more, and here’s a very important one that I didn’t now (being a Christian and not educated in much of the ways of Judaism) from 700 years ago: Abraham Ibn Daud ;
“God, he holds, limited his omniscience even as He limited His omnipotence in regard to human acts”
(on the wikipedia page about Gersonides)
” Rabbi Yeshayahu Horowitz explained the apparent paradox of his position by citing the old question, “Can God create a rock so heavy that He cannot pick it up?” He said that we cannot accept free choice as a creation of God’s, and simultaneously question its logical compatibility with omnipotence.”
Now wait, doesn’t this sound a bit arbitrary? From an information theoretical point of view I would characterize it as follows:
The universe can be deterministic i.e. God can know everything by advancing the computation of the state far enough yet we still have free will whether or not he chooses to do so: As free will is not the opposite of determinism: Free-willed decisions are based on past experiences, i.e. they are combinatorial in nature. Knowing the future (perfectly) is equivalent to realizing the future (due to computational irreducibility) (Therefore “Only God Knows”- He’s the only one who has a machine that can compute the future : The universe (or a copy of it))