This is the weekly Q & A blog post by our Research Professor in Philosophy, Dr. William Lane Craig.


Greetings Dr Craig

While reading question of the week #278, I noted that in your response to the issue of God's freedom yet inability to do evil, you argue by way of a classic Frankfurt Case that, in your words, "what is crucial to freedom of the will is not the ability to do the opposite but the absence of external causal constraints upon one’s choice". This of course is the credo of the compatibilist, who says that what matters is not the ability to do otherwise, but rather whether the decision is truly "up to you" in the sense of freedom from outside influence. I've been following your work for many years, and it was my strong impression that you are an incompatibilist and believer in libertarian freedom. But now I'm not so sure what your view is. Are you in fact a compatibilist? If so, surely you're aware of the implications this has for the free will defense to the problem of evil. Namely, the free will defense doesn't work on compatibilism because God could just determine everyone to always freely choose goodness and eternal life with Him. If you are not a compatibilist, why did you forward a classic argument in favor of compatibilism in question of the week #278?

Best regards,


United States

Dr. William Lane Craig’s Response

I am explicitly a libertarian about freedom of the will, and so there should be no doubt about that. I just deny the so-called Principle of Alternative Possibilities, that the ability to do otherwise in a given situation is a necessary condition of libertarian freedom. That’s the lesson of the thought experiments you mention.

So I take it that the compatibilist thinks that free will is compatible with my choice’s being causally determined by factors outside me. That’s why it's called “compatibilism”! My choice is causally determined but nonetheless free. I deny that, holding that a free choice cannot be causally determined by external factors.

I think you’re confusing coercion with causal determination. The compatibilist thinks that a free choice must be voluntary, something I want to do and so uncoerced. But voluntary choices are for the compatibilist still causally determined. Libertarians think that being voluntary is not a sufficient condition for free choice.

It’s incorrect that according to the compatibilist “what matters is not the ability to do otherwise, but rather whether the decision is truly ‘up to you’ in the sense of freedom from outside influence.” No, it’s freedom from coercion. As you yourself recognize, on compatibilism “God could just determine everyone to always freely choose” what one does. So the compatibilist does think that free choice is compatible with our choices’ being causally determined by external factors, in contrast to libertarians like me.

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