The Free Will Defense

The Free Will Defense is the most influential theistic response to the Problem of Evil. Developed by philosopher Alvin Plantinga in his 1974 book God, Freedom, and Evil, it argues that God permits moral evil because genuine free will is so valuable that a world containing free beings - even ones who sometimes choose evil - is better than a world of moral automatons. Most philosophers acknowledge that Plantinga successfully defeated the logical Problem of Evil, making this one of the most significant achievements in 20th-century philosophy of religion. However, major gaps remain, and the argument scores 40/100 for soundness.

The Core Argument

Plantinga’s defense can be stated in four steps:

1. Free will is a great good - so valuable that a world with free will is better than one without it, even accounting for the evil that free beings produce.
2. Genuine free will requires the real possibility of choosing evil. A being that can only choose good is not truly free.
3. It is logically impossible for God to create beings with genuine free will who are guaranteed to always choose good. Not even omnipotence extends to logical impossibilities.
4. Therefore, God is morally justified in permitting moral evil as the unavoidable cost of creating free beings.

The argument is technically a defense rather than a theodicy. Plantinga does not claim to explain why God allows evil. He only claims to show that God’s existence and evil’s existence are logically compatible - that there is no formal contradiction between them.

Transworld Depravity

Plantinga’s most original contribution is the concept of transworld depravity. He argues that it is possible that every possible free creature suffers from transworld depravity - meaning that in every possible world where that creature exists and is free, they would choose at least some evil. If this is the case, God cannot create a world with free beings and no evil, because every free creature would go wrong somewhere.

This is a modal claim about possibility, not a claim about what is actually true. Plantinga only needs it to be possible that every free creature is transworld-depraved to show that God and evil are logically compatible. Critics like J.L. Mackie initially argued the concept was incoherent, but most philosophers now accept it as logically possible, even if unlikely.

Why Philosophers Consider It a Success

The Free Will Defense is widely regarded as having resolved the logical Problem of Evil. Before Plantinga, atheist philosophers like Mackie argued that the statements “God is omnipotent,” “God is omnibenevolent,” and “evil exists” form a logically inconsistent set - that no possible world contains all three.

Plantinga showed this is false. There is at least one possible scenario where all three coexist: God creates free beings, free will is sufficiently valuable to justify the risk, and those beings freely choose evil. The logical contradiction vanishes. This shifted the philosophical debate from the logical problem to the evidential Problem of Evil - the argument that the amount and distribution of evil, while logically compatible with God, make God’s existence improbable.

The Natural Evil Gap

The most significant weakness is that the Free Will Defense only addresses moral evil - suffering caused by human choices like murder, cruelty, and theft. It says nothing about natural evil: earthquakes, tsunamis, childhood cancer, genetic diseases, parasites, and the millions of years of animal suffering before humans existed.

These sources of suffering involve no human free will. No one chose for tectonic plates to shift beneath populated cities. No one freely decided that children should develop leukemia. If God designed the natural world, these features are divine choices, not consequences of human freedom.

Plantinga later suggested that natural evil might be caused by the free choices of fallen angels or other non-human free agents. Most philosophers find this extension ad hoc and lacking independent support. It raises more questions than it answers - why would God grant demons the freedom to cause earthquakes but not prevent them from doing so?

The Scope Problem

Even granting that free will justifies some moral evil, the defense struggles with the sheer volume and extremity of suffering in the world. Could God not create free beings somewhat more inclined toward goodness without eliminating their freedom? Humans already vary enormously in their moral tendencies - some are naturally more empathetic, patient, or compassionate. A world populated with beings at the better end of human moral distribution would still contain free will and some evil, but far less suffering.

William Rowe developed this objection into the evidential Problem of Evil. Even if God and evil are logically compatible, the specific evil we observe - its intensity, its distribution, its apparent pointlessness - seems far beyond what free will requires. A child dying slowly of bone cancer serves no discernible free-will purpose.

The Heaven Problem

This may be the most difficult objection for the Free Will Defense. Most Christian theologians teach that heaven is a state where free beings exist without evil - the redeemed retain their freedom but never choose sin. If this is possible in heaven, why was it not possible on Earth from the beginning?

The defender faces a dilemma. Either heaven lacks genuine free will (which undermines its value and makes it less desirable than earthly life), or free will without evil is logically possible after all (which undermines the entire defense). Some theologians argue that earthly life is a necessary “soul-making” period that prepares beings for heavenly freedom, but this raises further questions about why an omnipotent God requires such a process and why it involves so much suffering.

The Problem of Hell intensifies this difficulty. If some free beings end up in eternal torment as a consequence of their free choices, the value of free will must be weighed against infinite suffering - and it becomes unclear whether free will is so valuable that it justifies an eternity of conscious torment for those who misuse it.

Compatibilism and Libertarian Free Will

The Free Will Defense requires libertarian free will - the view that human choices are genuinely undetermined, not the inevitable product of prior causes. If compatibilism is true - if free will is compatible with determinism - then God could have determined all beings to freely choose good. The defense collapses under compatibilism.

This is a significant vulnerability because compatibilism is arguably the dominant position among contemporary philosophers. The PhilPapers survey found that roughly 59% of professional philosophers lean toward or accept compatibilism. If they are right, God could have created a deterministic world where beings act freely (in the compatibilist sense) and never choose evil.

Plantinga acknowledges this dependence on libertarian free will and defends it, but the defense inherits all the philosophical difficulties of libertarianism, including how undetermined choices can be genuinely yours rather than random events.

Moral Responsibility Without Libertarian Freedom

Even setting aside the compatibilism debate, some philosophers question whether libertarian free will is necessary for moral development. John Hick’s soul-making theodicy suggests that what matters is the process of moral growth through facing challenges - but this could potentially be achieved without the extreme suffering that actual free will produces. If moral development is the goal, God could have designed creatures that develop morally through challenges calibrated to be productive rather than devastating.

The Logical vs. Evidential Distinction

Understanding the Free Will Defense requires distinguishing what it does from what it does not do. It demonstrates logical possibility - the mere compatibility of God and evil. It does not demonstrate plausibility, probability, or actuality. Showing that God could have a morally sufficient reason for permitting evil is very different from showing that God does have such a reason.

This is why the contemporary debate has shifted almost entirely to the evidential Problem of Evil. Philosophers like Rowe, Paul Draper, and others argue that even if God and evil are compatible in principle, the specific patterns of suffering we observe are much more likely on naturalism than on theism. The Free Will Defense does not address this probabilistic argument.

Influence on the God Debate

Despite its limitations, the Free Will Defense has shaped the entire field. It forced atheist philosophers to abandon the claim that God and evil are logically contradictory - a claim that had been central to atheist philosophy for decades. The debate moved to more nuanced territory, with both sides acknowledging that the relationship between God and evil is more complex than a simple logical contradiction.

The defense also influenced theological thinking. Many theologians now take the value of free will as a starting point for explaining evil, even when they supplement it with additional considerations like soul-making, divine mystery, or eschatological hope.

Our Scoring

The soundness score of 40/100 reflects the argument’s mixed performance. On the positive side, Plantinga genuinely solved the logical Problem of Evil - a significant philosophical achievement that most professional philosophers acknowledge. On the negative side, the defense fails to account for natural evil, struggles with the extreme scope of suffering, faces the devastating heaven problem, and depends entirely on libertarian free will, which is a contested metaphysical position. It also does nothing to address the evidential Problem of Evil, which is now the primary battleground.

The Personal God score of 50/100 is moderate because the defense, if successful, removes a major objection to a personal God’s existence. However, it does not positively establish that a personal God exists - it only shows that evil is not a knockdown argument against one. The removal of an objection adds some plausibility but is fundamentally different from providing evidence.

The Creator score of 50/100 matches the Personal God score. The defense is equally relevant to a creator deity, since the Problem of Evil applies to any being that designed the universe with the capacity for suffering. Removing the logical contradiction helps a creator concept to roughly the same degree.

The Higher Power score of 50/100 is identical because the Free Will Defense operates at the same level of abstraction for all three god concepts. It addresses whether any good, powerful being can coexist with evil - a question that applies equally regardless of how specifically the deity is defined. Unlike cosmological arguments that differentiate sharply between god concepts, the Free Will Defense’s logic applies uniformly across all three.