The argument in its strongest form

The argument is not a cheap slogan about God "making" people sin because He knows they will sin. Its strongest form is the classic problem of theological fatalism, developed in different ways by philosophers such as Nelson Pike, Anthony Kenny, Linda Zagzebski, and William Hasker. The issue is whether infallible divine foreknowledge is compatible with the kind of freedom required for moral responsibility.

Stated carefully, the argument runs like this. Suppose that long before Sarah's choice, it was already true that God infallibly knew Sarah would perform action A rather than action B. If God knows p, then p is true; an omniscient belief cannot be mistaken. The fatalist then adds a fixity principle: facts wholly in the past are not now within Sarah's power to alter. So if Sarah were now able to do B instead, she would seem to need a kind of power over the past -- either to make God's earlier belief false, which is impossible, or to make it the case that God had a different earlier belief, which also seems unavailable if the past is fixed. Therefore, Sarah cannot now do otherwise than A. If genuine responsibility requires such alternative possibilities, then it seems unjust to blame or punish her for A, or to praise and reward her for A, as though B remained open to her.

In Islamic vocabulary, the same structure is often expressed through qadar and al-Lawh al-Mahfuz: if all future acts are known and recorded before they occur, then the future appears fixed in advance. But in this discussion those terms function only as labels for a philosophical package, not as evidence for it. The question is whether the set of claims is coherent on shared rational grounds: God infallibly knows all future human choices; those choices are settled before the agents exist; agents are still free in the relevant sense; and God is just in holding them accountable.

The argument has real force because it connects three ideas many theists want to keep together: exhaustive divine foreknowledge, human moral responsibility, and justice. It is not enough to answer, "God knows but does not force." The fatalist will say that coercion is not the only threat to freedom. Even if God's knowing does not cause the act, the act may still be unavoidable if the past already contains an infallible truth about what the agent will do.

The formal shape of the problem

A simple version can be put as follows:

  • Yesterday, God infallibly believed that tomorrow Sarah will lie.

  • If God infallibly believes a proposition, that proposition cannot be false.

  • It is not now within Sarah's power to change hard facts about yesterday.

  • If God's yesterday-belief is one of those fixed past facts, then it is not now within Sarah's power to make it the case that God did not believe it yesterday.

  • Given that fixed belief and God's infallibility, Sarah will lie tomorrow.

  • So, if the relevant fixity principle and transfer of necessity are sound, Sarah cannot avoid lying tomorrow.

  • If moral responsibility requires the ability to avoid lying in that sense, then holding Sarah blameworthy for lying would be unjust.

The crucial move is from "God infallibly believed Sarah will lie" to "Sarah cannot avoid lying." The proponent is not merely saying that Sarah will lie. They are saying that, given the relevant fixed past facts and God's infallibility, there is no future accessible to Sarah in which she refrains. That is why the argument feels stronger than ordinary prediction. A weather forecast can be wrong. A human observer can misread a character. But an omniscient knower cannot be mistaken.

The argument also gains strength when divine foreknowledge is combined with divine decree or providential authorship. If God not only knows what will happen but also determines, ordains, or writes the complete order of events, then the concern shifts from foreknowledge to control. That is a related but distinct problem: foreknowledge by itself raises a modal worry about inevitability, while decree raises a sourcehood worry about whether the agent is the ultimate origin of the action. The more comprehensive the divine role in fixing history, the harder it becomes to maintain that human agents are ultimate sources of their actions in a libertarian sense.

The first major reply: foreknowledge is not causation

The standard theistic reply begins with an important point: knowing that something will happen is not the same as causing it to happen. If I watch a recorded football match and know the final score, my knowledge does not cause the players' actions. If a historian knows that Caesar crossed the Rubicon, her knowledge does not force Caesar to cross it. Knowledge tracks truth; it does not automatically produce truth.

This reply succeeds against a crude version of the argument. If someone says, "God knew I would do it, therefore God forced me to do it," that does not follow. Infallible knowledge, considered only as knowledge, is not coercion. The fatalist argument must be more subtle than that.

But the stronger fatalist is not claiming that knowledge causes the action. The claim is that infallible prior knowledge makes alternative action impossible. The issue is not causal compulsion but modal necessity. Could Sarah do otherwise, given that God's past belief is infallibly true? The "knowledge is not causation" reply is correct, but by itself it does not dissolve the problem.

A more powerful reply says that a quick version of the fatalist argument commits a modal mistake. The mistake is to slide from a necessary connection between God's knowledge and Sarah's act to the necessity of Sarah's act itself. From:

Necessarily, if God knew Sarah would lie, then Sarah will lie.

it does not follow that:

If God knew Sarah would lie, then necessarily Sarah will lie.

This distinction is old and important. The first statement says the conditional is necessary: God's knowing entails the truth of what is known. The second says Sarah's action itself is necessary. But entailment does not always transfer necessity to the consequent. If it is true that "if Sarah lies, then Sarah lies," the conditional is necessary, but Sarah's lying does not become necessary merely because the conditional is necessary.

Many defenders of compatibility between foreknowledge and freedom rely on some form of this response. Alvin Plantinga, for example, argues that a creature's freedom is not defeated merely by the fact that God knows what the creature will do. The key counterfactual claim is: if Sarah were freely to refrain from lying, God would not have had the belief that she would lie; God would have known the other outcome. This need not mean that Sarah causes God's belief or changes the past. It means that the truth of the divine knowledge claim is tied to what the free creature in fact does.

This reply has considerable strength. It shows that the fatalist cannot simply move from "God cannot be wrong" to "the agent cannot do otherwise" without further argument. Infallibility guarantees that God's beliefs match reality; it does not by itself explain whether reality is free, determined, or something else. But the reply is not a complete answer unless it also addresses the fatalist's further claim that the relevant past fact is now fixed and that this fixity transfers to Sarah's future act.

Still, the fatalist can press back. The problem is not only logical entailment but the fixity of the past. If God already believed yesterday that Sarah will lie tomorrow, then Sarah cannot now make it the case that God did not believe that yesterday. The past is no longer up to her. So how can the future still be up to her?

The Ockhamist reply: hard facts and soft facts about the past

One influential answer, usually traced to William of Ockham and developed in contemporary discussions by thinkers such as Marilyn McCord Adams and Alvin Plantinga, distinguishes between "hard" and "soft" facts about the past. In contemporary terms, a hard fact about the past is wholly about the past: that a tree fell yesterday, or that a person made a promise last week. A soft fact about the past is past-tense in grammar or temporal location but includes an essential reference to the future: that yesterday it was true that Sarah would lie tomorrow.

On this view, God's past belief about Sarah is a soft fact. It is temporally located in the past, but its content depends on what Sarah does in the future. If Sarah were to refrain freely, then the past would have contained a different divine belief. Sarah does not change the past. Rather, the past fact in question was never independent of her future action.

This is one of the strongest compatibilist replies to theological fatalism. It explains why the pastness of God's belief may not carry the same kind of necessity as ordinary past events. It also preserves the idea that God's foreknowledge is infallible without turning it into a causal chain that forces the act.

However, not everyone finds the hard/soft distinction satisfying. Critics argue that God's believing yesterday that Sarah will lie looks like a genuine past fact, not merely a future-dependent description. If Sarah has no power over God's past mental state, then it remains unclear how she has the power to do otherwise. The Ockhamist reply is sophisticated, but it depends on controversial claims about what facts are "up to us."

Timeless knowledge as another reply

Another classic answer, associated with Boethius and Aquinas, denies that God literally foreknows in the way we do. God is not located at an earlier time looking forward. Rather, God is timeless or eternal, knowing all temporal events in a single eternal act. On this view, God does not know Sarah's choice "before" she makes it. He knows it timelessly.

This avoids part of the fatalist structure, since the argument depends heavily on a past divine belief that is now fixed. If God's knowledge is not past, then the premise "the past already contains God's belief that Sarah will lie" is false.

This reply is philosophically serious, but it has costs. First, divine timelessness is itself controversial. It raises difficult questions about how a timeless being knows tensed facts, acts in history, responds to creatures, or has personal relations. Second, the fatalist may reformulate the worry without using temporal priority: even if God's knowledge is eternal rather than earlier, it is still infallible and not within Sarah's control in any ordinary sense. Some critics, including Zagzebski, argue that timeless knowledge may relocate the problem rather than remove it: if the complete truth about Sarah's action is eternally settled, in what sense is the alternative genuinely open?

What about justice and accountability?

The accountability argument depends on a particular account of moral responsibility. If free will requires the ability, at the very moment of action, to do otherwise in the exact same total circumstances, then infallible foreknowledge creates a serious puzzle. Libertarians such as Robert Kane emphasize this kind of openness, and on that model the fatalist challenge is powerful.

But not all philosophers accept that moral responsibility requires alternate possibilities. Harry Frankfurt famously argued that a person may be responsible even if they could not have done otherwise, provided the action issues from their own will in the right way. Many compatibilists hold that responsibility depends not on metaphysical openness but on whether the action flows from the agent's reasons, desires, character, and rational capacities without coercion or manipulation.

This matters because the argument "no alternate possibilities, therefore no accountability" is not universally accepted. If compatibilism is true, then even a determined or foreknown action can be morally attributable to the agent. A judge might fairly distinguish between a person acting from their own settled intention and a person acting under hypnosis, compulsion, or insanity, even if determinism were true in both cases.

That said, compatibilism also has its own burdens. If God's relation to the world includes not only knowing but determining every desire, motive, circumstance, and act, then the concern about justice becomes sharper. The agent may still be the immediate source of the action, but not the ultimate source. Whether that is enough for blame and punishment is a live dispute, not a settled matter.

What the argument establishes, and what it does not

The theological fatalist argument establishes a real pressure point inside classical theism. It is not refuted by saying "God knows but does not force." The deeper issue is whether infallible knowledge of future contingents is compatible with robust alternative possibilities and just accountability.

Still, the argument does not straightforwardly prove that God cannot exist. At most, it challenges a package of claims: exhaustive infallible foreknowledge, a settled future, libertarian free will, and a strong desert-based model of reward and punishment. A theist may revise the package in several ways: adopt Ockhamism, appeal to divine timelessness, accept compatibilist freedom, endorse Molinism by appealing to God's middle knowledge of counterfactuals of creaturely freedom, or deny that future free choices are presently knowable as settled facts -- a view defended by open theists such as Hasker and, in a related but not simply "open theist" form, by Richard Swinburne. Each move has costs, but none is obviously incoherent without further argument.

The fair conclusion is modest. The argument is strongest against the claim that humans possess libertarian freedom while every future choice is already infallibly fixed as part of a complete settled order. It is weaker against compatibilist accounts of responsibility and against models where divine knowledge is not a past event standing over the agent. It does not show that moral responsibility is impossible, nor that theism is false. It does show that any serious theistic account of omniscience, destiny, and judgment must explain exactly what kind of freedom humans have, and why that kind of freedom is enough for justice.