Problem of Evil

The problem of evil is the oldest and most enduring objection to classical theism. In its most general form, the problem asks how the existence of a God who is omnipotent, omniscient, and morally perfect can be reconciled with the suffering, cruelty, and apparent moral chaos observed in the world. If God has the power to prevent evil and the knowledge of how to do so, and if God is wholly good, then why does evil exist at all — and why does it exist in the magnitude and distribution we observe? The argument has been raised by theists and atheists alike across more than two thousand years of philosophical and theological reflection, and remains the single most discussed objection in contemporary analytic philosophy of religion.

The problem appears in Epicurus, who is reported by Lactantius to have posed the question in trilemma form, and is developed extensively in the Hellenistic period. It receives careful treatment in Augustine, whose response in the Confessions and the City of God draws on Neoplatonic resources, treating evil as privation (privatio boni) rather than positive substance. The medieval Islamic tradition engaged the problem under the rubric of divine justice (ʿadl) and human responsibility (kasb, istiṭāʿa), with extensive debates between Muʿtazila and Ashʿarī theologians on the relationship between divine omnipotence and moral evaluation. The Christian scholastic tradition, particularly in Aquinas, integrated Augustine's privation theory with Aristotelian metaphysics. Leibniz coined the term "theodicy" (from Greek theos + dikē, "justifying God") in his Théodicée (1710), defending the claim that this is the best of all possible worlds — a position famously satirized by Voltaire in Candide (1759).

In analytic philosophy of religion, the problem received its decisive modern formulation in J. L. Mackie's "Evil and Omnipotence" (1955), which presented the problem as a strict logical contradiction. Mackie argued that the propositions "God is omnipotent," "God is wholly good," and "evil exists" cannot all be true together. Alvin Plantinga's response in God, Freedom, and Evil (1974) was widely taken to defuse the logical version: Plantinga's free will defense argued that it is logically possible that God could not create a world containing moral good without also permitting moral evil, and this possibility is sufficient to block Mackie's contradiction claim. Following Plantinga, the philosophical debate shifted toward the evidential problem, formulated most influentially by William Rowe in "The Problem of Evil and Some Varieties of Atheism" (1979), which argues that even if the logical problem fails, the sheer quantity and distribution of apparently pointless suffering provides strong probabilistic evidence against the existence of a perfect God.

Theistic responses to the evidential problem have taken several forms. Skeptical theism, developed by Stephen Wykstra, William Alston, and Michael Bergmann, argues that human cognitive limitations prevent us from reliably judging which apparent evils lack justifying reasons; the move from "we see no good reason" to "there is no good reason" is epistemically unwarranted given our limited perspective. John Hick's soul-making theodicy proposes that suffering plays a necessary role in the moral and spiritual development of free creatures. Other theodicies appeal to greater goods, free will, the eschatological completion of justice, or various forms of divine hiddenness. Critics including William Rowe, Paul Draper, Wes Morriston, and J. L. Schellenberg have responded to each of these defenses with detailed counter-arguments. Schellenberg's distinct argument from divine hiddenness — that the existence of non-resistant non-believers is itself evidence against God — has emerged as a substantial sister-problem deserving its own analysis.

The family contains seven principal formulations differing in their precise inferential targets. The Logical Problem of Evil claims that evil and a perfect God are logically incompatible, the Plantinga-era target now widely considered superseded. The Evidential Problem of Evil claims that observed evil makes God's existence improbable rather than impossible. The Free Will Defense and Soul-Making Theodicy are theistic responses developed within the family as principal counter-positions. The Natural Evil Problem focuses on suffering not caused by human agency — animal suffering, natural disasters, disease — which resists free-will accommodation. Skeptical Theism is the metaepistemological response defending agnosticism about apparent evils' justification. The Hiddenness of God presents Schellenberg's distinct but related argument: the absence of clear divine self-disclosure to non-resistant inquirers itself counts against God's existence.

Within god-database, the problem of evil belongs to the transversal maslik (Maslik 0), since it crosses every other path of inquiry: it challenges philosophical arguments (Maslik 1) by questioning the coherence of theistic concepts, cosmic arguments (Maslik 2) by complicating the inference from cosmic order to a benevolent designer, human arguments (Maslik 3) by raising the question of moral fittingness, and prophetic and textual arguments (Masāliks 5-6) by demanding that revealed traditions address the suffering their readers actually experience. The strength of the cumulative case for theism depends importantly on how convincingly defenders meet the cumulative force of these formulations.