Foreknowledge and Free Will
God is sometimes characterized as omniscient, and his omniscience is sometimes taken to include knowledge of the future–of all future events. But his foreknowledge of events, it is sometimes argued, is logically inconsistent with human beings’ having freedom of the will. After all, if God already knows what will happen, how can we have any real choice in the matter? We must choose exactly in accordance with God’s foreknowledge.
The simple argument for the incompatibility of God’s foreknowledge with human freedom of the will, using “Np” to represent “metaphysically necessarily p,” “Pp” to represent “metaphysically possibly p,” “x” to represent “x occurs at time t,” and “Kx” to represent “it is known that x occurs at time t,” is
1. N(Kx—>x) (Premiss—to know that x will occur at t requires that x will occur at t)
2. Kx—>x (1, modal axiom M [or T], i.e., Np—>p)
3. Kx (Premiss—it is known that x occurs at t [since God has complete foreknowledge])
4. x (2, 3, modus ponens)
Hence, if we assume that event x at t is foreknown, we know that event x at t occurs—and, therefore, not event not-x at t. But where is human freedom if what is foreknown dictates what occurs?
The problem with this can be shown if we simply take “Kx” to denote postknowledge instead of foreknowledge. The same argument works just as well, and yet we don’t think that postknowledge dictates the event x’s occurrence at t. Rather, we think that event x’s occurrence at t dictates which of “x occurs at t” and “not-x occurs at t” is known. For an omniscient postknowing being, x dictates Kx, and not-x dictates K(not-x). We might similarly say that for an omniscient foreknowing being, x dictates Kx, and not-x dictates K(not-x)—i.e., that whether x or not-x happens at time t determines whether x is known or not-x is known, even if the knowledge is foreknowledge instead of postknowledge.
Yet, there’s a clear asymmetry between the cases of foreknowledge and postknowledge. If a person A makes the choice between x and not-x at time t, and if, at some later time, a postknower tells person A which choice he made, we see nothing strange about it, and it certainly doesn’t affect how we think of person A’s freedom to choose. On the other hand, if a foreknower tells person A which choice he will make, there is a problem: Why can’t person A just be contrary and choose to act otherwise than he has been told he will? If he can do so, then he has the power to render foreknowledge false, which surely can’t be done; if he cannot do so, then he doesn’t seem to be choosing freely.
It seems that if foreknowledge is to be compatible with freedom of the will, any foreknower is limited in what he can do between the moment of his first attaining foreknowledge and the time t when x is chosen. In particular, he cannot initiate a chain of events that might lead person A to do what he otherwise would not do. The simplest way to ensure this would be for the foreknower to remain passive.
Do we, then, limit God, so that although his omniscience extends to complete foreknowledge of events, he does not exercise any power he might have over the course of human events? (While this might be a stronger restriction than really necessary, it seems like an aesthetically pleasing choice.) Do we instead say that God’s omniscience does not extend to knowledge of future events?
May 11th, 2008 at 2:20 am
The simple solution for the defender of divine foreknowledge to the argument as you outlined it is to point out how, even if sound, the argument doesn’t negate creaturely freedom. This is because the necessity in (1) does not carry over to the conclusion, (4). But carrying necessity to x, at least in the argument as you’ve outlined, would be guilty of an invalid modal operator shift. As it stands, all that follows is x, not Nx. In other words, (4) still allows for possibly ~x, which is entirely consistent with creaturely freedom. What you need is an argument that establishes Nx.
May 14th, 2008 at 10:43 am
It seems to me that although Nx is not established, it is also not needed. In every possible world, we have Kx—>x and K(~x)—>~x, so whether x or ~x is foreknown (in particular, which is foreknown by God) fixes whether it is x or ~x that occurs.
As long as neither Nx nor N(~x) has been established, one may say, as I suggested, that the foreknower’s knowledge is the result of the agent’s freely choosing x or, alternatively, freely choosing ~x, even though there is no escaping the complete correlation between what is foreknown and what is chosen; one may say that although the agent’s choice is temporally fixed before he makes it, it is ultimately metaphysically fixed by his own choice, which in turn makes the foreknower foreknow what he foreknows. But a problem does arise if the foreknower (in particular, God) tells the agent which choice he is going to make. Why can’t the agent, upon being told which choice he’ll make, simply be contrary and choose the opposite? That’s where the problem arises.
June 25th, 2008 at 1:03 am
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