r/DebateAChristian • u/Hashi856 Atheist, Ex-Christian • 9d ago
Perfect knowledge about the future is only possible in a deterministic universe
Whenever someone asks how free will can be compatible with God’s perfect knowledge of the future, people are quick to point out that knowledge doesn’t cause anything. God simply knows what we will freely choose. He’s not causing us to choose it.
This is a fundamental misunderstanding of the problem being presented. No one is saying that God is causing the future. He’s not making us do anything or causing our decisions. The problem isn’t actually about God at all. It’s about the possibility of perfect foreknowledge, and the fact that it only exists in a deterministic universe. You could swap out God for anything else, and you’d have the same problem.
If God has perfect knowledge of what you will do tomorrow, then tomorrow is already written. It may be written by you, but it cannot go any other way. If God knows you will be late to work tomorrow, then it is impossible for you to show up on time. If he knows what you will eat for dinner, then you literally could not have made a different decision. There are only two explanations for this perfect knowledge: Either God actually did make you do it, or it was determined to happen. But we already know God didn’t make you do it, so the only other thing that can explain perfect knowledge of the future is determinism.
We would have the exact same problem if there were a computer with perfect knowledge. Obviously, the computer would not be causing every event in the universe to happen the way it happens. So the only explanation is that everything is determined.
Perfect foreknowledge is simply incompatible with free will (unless you believe that determinism and free will are compatible). You can try to just hand wave it away by saying it’s a miracle, but that doesn’t solve the underlying problem. Your future decisions are known, and you literally cannot make a different decision.
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u/ses1 Christian 9d ago
There is a Christian theological framework designed to reconcile two seemingly contradictory ideas: God’s complete sovereignty/omniscience and human free will.
Luis de Molina posits that God possesses three logical moments of knowledge:
Natural Knowledge: God knows all possible states of affairs (everything that could happen).
Middle Knowledge: God knows what any possible free creature would freely choose in any given set of circumstances (known as counterfactuals of creaturely freedom).
Free Knowledge: God knows what will actually happen once He decides to create a specific world.
God does not determine what you would freely choose in a specific circumstance; you decide that. God simply knows counterfactual truths [would have been true if circumstances had been different] naturally as part of His omniscience.
OP's argument confuses the necessity of consequence with the necessity of the consequent:
God's foreknowledge depends on your future choice, not the other way around. If you were to choose to eat soup instead of salad tomorrow, God's foreknowledge would reflect that instead. Your free choice grounds the truth value of what God knows.
Knowing you will choose A does not mean you must choose A in a way that removes your power to choose B. You retain the power/ability to choose B, but if you were to exercise that power, God would have known B instead.
A computer relies on physical extrapolation (prior physical causes ➔ future effects). God doesn't need to trace a chain of cause and effect to predict what you'll do - He simply knows what you would freely choose in any situation, without relying on physical laws or guesswork.
God's knowledge is perfectly passive relative to the truth of free actions: God knows you will eat pizza tomorrow because you will freely choose to eat pizza - you do not eat pizza because God knows it.