Philosophy of Evil

Meaning and Origins

The philosophy of evil is the branch of philosophy that asks what evil is, where it comes from, and whether it can be reconciled with the existence of a good and all-powerful God. It is the hardest problem in the philosophy of God and the most powerful argument in the philosophy of atheism. If God is perfectly good, God wants to prevent evil. If God is all-powerful, God can prevent evil. Evil exists. So either God isn't good, or God isn't powerful, or God doesn't exist. That, in compressed form, is the problem.

The problem has ancient roots. The Greek philosopher Epicurus framed it in a form that Hume later made famous: God either wishes to prevent evil and cannot, in which case God is not omnipotent; or God can prevent evil and does not, in which case God is not perfectly good. Augustine responded by developing the privation theory of evil: evil is not a positive substance but the absence of good, much as darkness is the absence of light. A perfectly good God did not create evil; evil arises when rational creatures misuse their God-given freedom, turning away from the good and toward nothing. This account dominated Western theology for over a millennium and provided the conceptual framework for what would later be called theodicy — the justification of God in the face of evil.

Core Ideas

The Logical Problem of Evil

The logical problem of evil, as formulated by J. L. Mackie in 1955, claims that the existence of evil is logically incompatible with the existence of an omnipotent, perfectly good God. Mackie argued that a good God would eliminate evil as far as it could, an omnipotent God could eliminate all evil, and therefore if God exists, there should be no evil. The appearance of evil in the world means either God lacks the will to eliminate it (not good) or the power to eliminate it (not omnipotent).

This is a strong claim — it says theism is logically incoherent, not merely improbable. To defeat it, the theist needs only to show that there is a possible world in which God and evil coexist — that is, to show that God might have a morally sufficient reason for permitting evil. The most successful response is the free will defense, developed by Alvin Plantinga. Plantinga argued that genuine free will is a great good, and that even an omnipotent God cannot cause free creatures to always choose the good — doing so would be logically contradictory, since a free action is one that could have been otherwise. If God wants free creatures, God must accept the possibility that they choose wrongly, and the evil that results is a consequence of freedom, not a limitation of divine power. Plantinga's defense is widely regarded as having defeated the logical problem of evil, though the debate continues.

The Evidential Problem of Evil

With the logical problem largely resolved, contemporary discussion has shifted to the evidential problem. This version, most influentially developed by William Rowe, concedes that God and evil aren't strictly incompatible but argues that the amount and distribution of suffering in the world makes God's existence improbable. The existence of a fawn burning in a forest fire, or of a child dying slowly of cancer, doesn't serve any greater good that we can see. If God existed, we'd expect to see less pointless suffering. The fact that we see so much of it is evidence against God.

The evidential problem is harder to answer because it doesn't claim logical incompatibility — it claims that the evidence, weighed as a whole, favors non-belief. Theistic responses include the skeptical theism of Stephen Wykstra (we are not in a position to judge what goods God might be pursuing, since our perspective is limited) and the soul-making theodicy of John Hick.

Theodicy and Defense

It's important to distinguish between a theodicy and a defense. A defense shows that God and evil are compatible — it's a logical point. A theodicy explains why God actually permits evil — it's an explanatory point. The free will defense is technically a defense: it shows what God's reason for permitting moral evil might be, without claiming to know that this is in fact God's reason. A theodicy goes further, claiming to explain the actual purpose of evil.

The most influential modern theodicies are the Augustinian theodicy and the Irenaean (or soul-making) theodicy. The Augustinian theodicy, developed by Augustine and refined by Aquinas, holds that evil entered the world through the free choice of rational creatures and that God permits it as the necessary condition of a world with genuine freedom. The Irenaean theodicy, developed in modern form by Hick, holds that the world is designed as an environment for soul-making — the development of moral and spiritual character through struggle, suffering, and growth. Hick argued that a painless world, a "pleasure planet," would not produce the moral virtues — courage, compassion, forgiveness — that are the point of human existence. Suffering is the necessary condition of soul-making, and God permits it because soul-making is a greater good than a painless existence.

Natural vs Moral Evil

The philosophy of evil distinguishes between moral evil and natural evil. Moral evil is suffering caused by the free choices of rational beings — murder, betrayal, cruelty. Natural evil is suffering caused by non-rational processes — earthquakes, disease, floods, decay. The free will defense explains moral evil but struggles with natural evil: if the fawn in the forest fire isn't suffering because of a human choice, how is it compatible with God?

The Augustinian tradition had an answer: natural evil is a consequence of the fall, the corruption of the whole created order by the first human sin. This answer requires a strong doctrine of original sin and a literal fall, which many contemporary philosophers find hard to accept. Hick's soul-making theodicy offers an alternative: natural evil is the necessary condition for soul-making. Courage requires danger, compassion requires suffering, patience requires frustration. A world without natural evil would be a world without the conditions for moral growth.

The Soul-Making Approach

Hick's approach, drawn from the early Church father Irenaeus, represents a fundamental reframing of the problem. Instead of asking why a perfect world contains evil, Hick asks: what if the world isn't meant to be a pleasure garden but a place for moral development? On this view, the question "Why is there suffering?" gets a different answer: because soul-making requires it. The world is a vale of soul-making, and the evils we encounter are the necessary conditions for the growth of the human spirit toward its intended fulfillment. Hick's theodicy has been criticized for seeming to justify all suffering, for the problem of those whose suffering destroys rather than develops them, and for the question of whether the amount of suffering in the world is really proportionate to the soul-making it enables. But it remains one of the most thoughtful and humane responses to the problem.

The Philosophy of Evil and the Wider Conversation

The philosophy of evil doesn't stand alone. It's the most powerful objection within the philosophy of God — if evil defeats God, theism falls. It's the strongest argument in the philosophy of atheism — the existence of suffering is evidence, if not proof, against the divine. It connects to ethics through the question of moral evil: what makes an action or a person genuinely bad? And it touches the philosophy of faith, which asks whether belief in God can be rational even in the face of unresolved suffering. The religion, God, and the sacred collection gathers these threads into a complete learning path.

Sources

• Stanford Encyclopedia of Philosophy, "The Problem of Evil."
• Stanford Encyclopedia of Philosophy, "Philosophy of Religion."
• Stanford Encyclopedia of Philosophy, "Augustine."
• Stanford Encyclopedia of Philosophy, "Original Sin."
• Stanford Encyclopedia of Philosophy, "David Hume."