Alvin Plantinga’s Free Will Defense

Why would a good God permit evil? Ultimately, I don’t think we can ever get to a proof of God’s existence through logic and the problem of evil in the world is the best argument against God.

The problem of evil argues that the existence of an all-powerful and all-good God is incompatible with the existence of evil in the world. In other words, if God is both all-powerful and all-good, why doesn’t God simply eliminate evil altogether? If you wonder why I think this is the best argument against theism, spend five minutes contemplating childhood leukemia or the Holocaust.

What is Alvin Plantinga’s Free Will Defense?

Alvin Plantinga, a contemporary American philosopher and leading figure in analytic philosophy of religion, is renowned for his “free will defense,” reconciling divine omnipotence with human freedom in the face of evil. People are still debating these rich ideas but I have become convinced that Plantinga’s arguments successfully rebut the problem of evil. Even though I think the problem of evil is the most convincing argument for atheism, Plantinga has removed my concerns about it in my own thoughts about God and theism.

A big caveat: I’m trying to dumb down this argument for a blog article so that will make it a little rough and maybe dull some of the logical edge it provides. This is an overview and if you want to go deeper you could read Plantinga’s book, God, Freedom and Evil. It’s a relatively short book of grad-school-level difficulty that any reader of this blog could handle.

Alvin Plantinga’s Free Will Defense is not an argument for God’s existence. Instead, it is an argument against the problem of evil. It suggests that the existence of evil doesn’t contradict the nature of an omnipotent, omniscient, and omnibenevolent God, but rather is a necessary consequence of allowing true moral freedom. Here are the biggest ideas.

Possible Worlds

When Plantinga talks about possible worlds, he doesn’t have the multiverse of madness in mind. At least I don’t think he does. He is introducing an idea that we can imagine an infinite number of ways that God could have established the universe. There could be a world with different laws or initial conditions after the big bang. The possible worlds that we imagine are just scenarios that could potentially exist with different combinations of choices, circumstances, evolution and more. This argument only sets up that fact that God had infinite possibilities in setting up creation, it is not a theological commentary on God’s creative process. In other words, maybe other universes exist or existed, we’re only concerned with the fact that we can imagine that our universe could have been vastly different. He sets up this argument to later demonstrate that just as God cannot make a stringless guitar — assuming you define a guitar as a stringed instrument and not one of these — an omnipotent God is not free to make a universe designed for greater good without free will.

Moral Freedom

Do we have free will? That is a great question and many people believe that we do not. Maybe you’re an atheist who believes that instinct and chemicals predetermine most of our choices and we just suffer from the illusion that we have free will. Maybe you’re a theist who believes God has mapped out a plan for you and that limits your conception of free will. What Plantinga is asserting here is that if you believe in the possibility of moral freedom – the ability to truly choose between good and evil even occasionally – then you must accept the possibility to choose evil. If you couldn’t choose evil, you wouldn’t be making a truly free choice.

Plantinga is essentially asserting that free will is incompatible with determinism, the philosophy that your choices or the events around you are predetermined by preceding events that set off a chain of causation, perhaps such as biology and underlying natural laws. A majority of philosophers hold a compatibilist view of free will which might conflict with Plantinga, stating that it is possible to have free will but also have determinism. One approach to understanding their point of view, albeit in a very crude manner, is to ponder if free will is possible in every situation in an evil world. Do you have perfect free will if you were raised in poverty, by evil parents, in a totalitarian state or with poor health? Are some of the choices you make truly free, or are they predetermined by events beyond your control even if you would ordinarily make free choices without those constraints?

I think if you hold that you have free will in any possible circumstance, you also have to hold that you are capable of making the wrong choice in those circumstances. Plantinga used a great metaphor when describing why he thought compatibilism was not logically valid: “…One might as well claim that being in jail doesn’t really limit one’s freedom on the grounds that if one were not in jail, he’d be free to come and go as he pleased.” In other words, if determinism is true (we’re all in jail), it doesn’t matter that you have free will in other circumstances. If determinism is only sometimes true, then you have to allow for at least occasional real world free moral choices and thus the possibility of evil.

You could also argue against Plantinga by saying there is no moral absolute right or wrong, but in that case, you are also eliminating the problem of evil altogether. If there is no actual evil, there is no problem.

Plantinga’s arguments directly address human evil – I think quite convincingly. But he doesn’t really address natural evil and suffering – cancer, hurricanes and earthquakes.

Greater Good

The hardest part for most people to swallow in Plantinga’s argument is his argument that whatever world we are living in, it works for the greater good. Simply put, a world with beings who have moral freedom is better and more valuable than a world without free will. And from his argument about moral freedom requiring the ability to choose evil, evil must exist in a world that finds its greater value in moral freedom. The main critique of this position is that human free choice may not actually represent the greater good for all of creation. Millions of extinct species would like a word. Some might also argue that an all-powerful God should be able to create a world where people have free will yet evil doesn’t exist. More on that next under God’s Omnipotence. For now, consider love, kindness, compassion and other moral virtues. These only have meaning in a world where they can be freely chosen. Otherwise, they are just robotic responses programmed by God or nature. Allowing for these virtues requires allowing evil. Plantinga is asserting that the possibility of love in any expression results in greater good than the possibilities of evil.

God’s Omnipotence

One of the most influential pastors in my life shocked me when I was younger by saying he didn’t believe God was omnipotent. He might have also disagreed with God’s omniscience because he was a process theologian, but that is a discussion for another day. What I think he meant by dismissing God’s omnipotence is not that God isn’t all powerful. Instead, God may choose to self-limit that power. To me this is the very image of Jesus on the cross. God limits God’s own power for our freedom, for our love and for our maximum potential. I believe what Plantinga is arguing here is that if God prevented evil actions, it would also prevent free will, which would not be the greater good where true love is possible. God limits God’s own power where it would infringe on free will. Just as an omnipotent God could not create a triangle with five sides — nor a stringless guitar — God cannot create a loving being without allowing the possibility of evil.

Summary of the Argument

There are possible worlds we can imagine that are not possible for God to create if the greater good requires love and moral freedom. Love requires moral free will, but that free will must allow for evil choices as well.

This argument has been widely accepted as disposing with the problem of evil as an airtight argument against God. That is, the problem of evil no longer logically disproves God – God can logically exist even in a world of evil. That doesn’t prove God exists, but it demonstrates God can be logically possible even with the presence of evil. So why do so many atheists still say the problem of evil is what keeps them from theism? Emotionally, I resonate with them, especially in areas that involve child suffering. Suffering is different than evil and suffering is not addressed here. Earthquakes are not addressed here.

Some believe that Plantinga is just wrong about either God’s omnipotence or about free will. They might argue that a truly omnipotent God could “figure it out.” Or, that free will could still exist in a world where only morally good choices exist. To me, Plantinga has sufficiently addressed those arguments but I’m still sympathetic to people who disagree.

This argument doesn’t prove God, it just makes the existence of God logically possible and not inconsistent with a world of evil. Christianity directly addresses evil in its theology, so once you’re over the problem of evil, I find Christianity very compelling. I love that we gather every week to confess our sins and remember that Jesus – and the rest of us – save the world through forgiveness. I love that we worship a God who, in the face of evil, instead of eliminating free will and thus eradicating real love, chose to suffer evil and die with us. Our hope is not in the elimination of present evil but in its complete defeat.