Theodicy: The Problem of Evil as a Logical Challenge
Of all the arguments against the existence of an omnipotent, omniscient, and perfectly good God, the problem of evil has the longest philosophical pedigree and the most immediate grip on ordinary intuition. It is worth examining carefully, because both its force and its limits are routinely misrepresented.
The logical and evidential versions
Philosophers distinguish two forms of the argument. The logical problem of evil, associated with J.L. Mackie's 1955 paper, claims that the existence of any evil whatsoever is strictly incompatible with a God who is omnipotent and omnibenevolent. If God can prevent evil and wants to, evil should not exist. Since evil does exist, such a God does not. This is a deductive argument: if the premises are true, the conclusion follows necessarily.
The evidential problem of evil, developed most rigorously by William Rowe, makes a weaker but harder-to-dismiss claim. It does not assert strict logical incompatibility. Instead it argues that the amount, distribution, and gratuitousness of suffering in the world makes the existence of a good God improbable. Rowe's focus on gratuitous suffering—evil that serves no greater purpose—is the sharper edge of this version. A fawn burning to death alone in a forest fire, unobserved and beyond help, is his canonical example.
The free will defense and its reach
The most widely offered theistic response to the logical problem is the free will defense, developed systematically by Alvin Plantinga. The core move is that an omnipotent God cannot create beings with genuine libertarian free will and simultaneously guarantee they will never choose evil. Freedom and guaranteed right action are incompatible, so even an omnipotent being cannot produce both. God's allowing moral evil is therefore consistent with perfect goodness.
This reply has considerable force against the logical problem, and most philosophers now regard Mackie's strict incompatibility claim as unsuccessful. But the free will defense has clear limits. It addresses moral evil—suffering caused by human choices—but says nothing about natural evil: earthquakes, childhood cancers, parasites that blind children, the five mass extinctions that preceded human existence. These cannot be attributed to human freedom. Theodicies that extend the free will defense to natural evil—by positing demonic agency or claiming that physical regularity is itself necessary for free agency to function—introduce independent theological commitments that require their own defense.
Soul-making and greater-good theodicies
A different family of responses, associated with John Hick drawing on Irenaeus, holds that suffering is instrumentally necessary for the development of morally serious persons. On this soul-making theodicy, a world without hardship, risk, and genuine loss would produce shallow characters incapable of courage, compassion, or genuine virtue. God permits suffering because it is the precondition of a valuable kind of human flourishing.
The response has intuitive appeal—there is something to the idea that adversity builds character—but it faces serious objections. First, the sheer quantity and distribution of suffering seems wildly disproportionate to any plausible soul-making purpose. Children who die in infancy, people rendered comatose by injury, animals with no apparent capacity for moral development: these cases do not fit the soul-making story without considerable supplementary argument. Second, the theodicy assumes that God could not produce the relevant kind of character through less destructive means, an assumption that is difficult to justify given the unlimited power attributed to God. Third, critics note that the theodicy treats real individuals as instruments for spiritual development, which sits uneasily with accounts of divine love that emphasize persons as ends in themselves.
What skeptical theism concedes
The most sophisticated contemporary theistic response to the evidential problem is skeptical theism, defended by Michael Bergmann, Michael Rea, and others. The argument is epistemological rather than constructive: humans are not in a position to judge whether apparently gratuitous evils are truly gratuitous, because our cognitive access to the full range of possible goods, possible evils, and their interconnections is radically limited. The fact that we cannot see what greater good a particular suffering serves does not establish that no such good exists.
Skeptical theism successfully shifts the burden of proof, and that is a genuine achievement. But critics press a significant cost: if human cognitive limitations prevent us from inferring that God would prevent gratuitous evil, the same limitations would seem to prevent us from making reliable moral judgments at all. Stephen Wykstra and his critics have debated this carefully, and the exchange remains unresolved. There is also a practical worry: a theodicy grounded in our ignorance of God's reasons provides no resources for moral objection to suffering, which many theists are unwilling to accept.
The problem of evil does not straightforwardly refute theism, and honest inquiry requires acknowledging that. What it does is raise the cost of maintaining a specific kind of theism—one committed to omnipotence, omniscience, and perfect goodness all at once—in the face of a world that looks, on its surface, exactly as one would expect if no such God existed.
