Evil and Genuine Free Will

Plantinga's free will defence is at its most persuasive when applied to moral evil: the argument that genuine freedom logically requires the possibility of choosing evil is coherent and largely survives Mackie's challenge, though it depends on an incompatibilist view of freedom.

Plantinga argues that to give creatures genuine free will, God must allow them to choose evil as well as good; a being that was programmed or determined to choose good would not be free in any meaningful sense. As he puts it, "to create creatures capable of moral good, God must create creatures capable of moral evil." Furthermore, Plantinga argues that God could not have created a world where all free creatures always freely choose good: this would be a logical contradiction, since if God determined what they chose it would not be free choice, and if they were free they might choose evil. The world with free creatures who sometimes choose evil is therefore not a failure of God's power but a logical consequence of a genuinely good gift.

J.L. Mackie challenges this directly in "Evil and Omnipotence": if God is omnipotent, why could he not have created free beings who always freely choose good? Mackie argues that an omnipotent God should be able to bring it about that free creatures always make the right choices — their freedom and their goodness need not be in tension. He also raises the concern that if we accept that a higher-order good (freedom) justifies a first-order evil (wrongdoing), this opens an infinite regress: we may need higher-level evils to justify higher-level goods without end.

Plantinga's response to Mackie is philosophically compelling: Mackie's "always freely choose good" scenario is logically incoherent — if God ensures the outcome, the choice is not free. This depends on an incompatibilist view of freedom (that genuine freedom requires the absence of determining causes), which Plantinga adopts. He also introduces the concept of "transworld depravity": it may be that in any world God could have created containing free creatures, at least some of them would sometimes choose evil, making a world of free creatures with no evil literally impossible for even an omnipotent God to produce.

Plantinga's response is largely successful against Mackie's specific challenge: if we accept incompatibilism, the claim that genuine freedom requires the possibility of evil is convincing. However, the argument's dependence on incompatibilism is itself a weakness: compatibilists (including Hume and many contemporary philosophers) argue that freedom is compatible with determined choices, provided the determination comes from within the agent's own character and desires. If compatibilism is correct, God could have created free beings whose characters were always inclined towards good without eliminating genuine freedom. The free will defence for moral evil is therefore convincing on its own terms but not universal, since it requires accepting a contested philosophical position about the nature of freedom.

So the claim that evil is necessary for genuine free will is convincing as applied to moral evil, but only if we accept an incompatibilist conception of freedom — a significant qualification that limits its persuasive range.

The free will defence is significantly less convincing when applied to natural evil — earthquakes, disease, tsunamis — since these are not caused by human free choices, yet they constitute a major part of the evidential problem of evil.

Natural evil presents a direct challenge to the free will defence: even if human freedom explains why God permits moral evil, it cannot explain why God permits earthquakes, childhood cancers, or the Lisbon earthquake of 1755 that killed 60,000 people, none of which is the result of human free choices. Plantinga's only response within the free will framework is to suggest — somewhat speculatively — that natural evil might be caused by fallen angels exercising their free will to corrupt the natural world. While this technically extends the free will defence to natural evil, it requires positing demons as the cause of plate tectonics and genetic mutations, which most find empirically and philosophically implausible. John Hick, developing Irenaeus' soul-making theodicy, offers a different and arguably better account of natural evil: it is necessary not because of free will but because a challenging, unpredictable environment is required for the development of virtues such as courage, compassion and perseverance.

However, Hick's soul-making account of natural evil faces its own serious challenges. First, it struggles to account for dysteleological evil — suffering so extreme, random or disproportionate that it seems to serve no soul-making purpose. The Holocaust, the suffering of infants who die before developing any virtues, and geological catastrophes that kill indiscriminately do not look like carefully calibrated moral education. As D.Z. Phillips argues, the idea that God uses innocent suffering as a tool for the spiritual development of others is morally monstrous — it treats innocent sufferers as mere means to other people's ends. Second, it is not obvious that natural evil is necessary for soul-making: God could presumably have created beings who develop virtue through challenges that do not involve innocent suffering, such as purely non-harmful difficulties.

Hick responds that a world perfectly safe, free from all danger and challenge, would produce beings incapable of genuine moral development — what he calls "human pets" rather than moral agents. If virtue is only valuable when chosen and exercised under genuine risk, then some real natural challenge is logically necessary for genuine soul-making, not merely instrumentally convenient. On dysteleological evil, Hick appeals to eschatological justification: the ultimate goodness of God's plan will only be fully apparent in the afterlife, where the suffering of this life will be redeemed. This does not deny the horror of dysteleological evil but insists it is not the final word.

Hick's eschatological response is honest but epistemically unsatisfying: it essentially asks us to trust that an ultimate justification exists without being able to specify what it is, which is a very weak evidential position. The free will defence's response to natural evil via fallen angels is even weaker, requiring empirically implausible metaphysical claims. The most convincing overall conclusion is that natural evil remains the hardest case for any theodicy involving free will: the claim that evil is necessary for genuine free will is partially convincing for moral evil but largely fails to address the full scope of evil in the world, particularly the suffering of innocents through natural causes.

Thus, the claim that evil is necessary for genuine free will is convincing in a narrow domain but insufficient as a complete theodicy, since natural evil requires a different justification that neither the free will defence nor Hick's soul-making fully provides.