Even if each instance of suffering is not individually logically inconsistent with God’s existence, the collective force of the evidence can make the hypothesis of a loving God so improbable that belief in such a God would itself conflict with what a loving God would expect from rational creatures.
This argument turns on a principle many theists already accept:
A loving God would not set up the world so that the most reasonable conclusion for a morally and intellectually responsible agent is that God probably does not exist.
THE ARGUMENT
Philosophical discussions of the problem of evil traditionally distinguish between two forms of argument. The logical problem of evil attempts to show that the existence of any evil at all is strictly incompatible with the existence of an all-powerful, all-knowing, and perfectly loving God. The evidential problem of evil, by contrast, does not claim contradiction; instead, it argues that the amount, intensity, or distribution of suffering in the world makes God’s existence highly improbable. Although these approaches are often treated as distinct, the evidential argument can, under entirely reasonable assumptions, generate a logical argument. In this sense the evidential and logical problems of evil are not rivals but stages of a single line of reasoning.
Supporters of the evidential argument often focus on specific categories of suffering. Some claim that any suffering whatsoever is at least some evidence that God’s perfect love is improbable. Others take a more restricted view and focus on types of suffering that seem especially resistant to theological justification. They point in particular to two troubling classes of evil: (1) suffering that gives the victim no opportunity to grow morally, spiritually, or psychologically, and (2) suffering that is extraordinarily intense or prolonged, far beyond what would be required for any conceivable moral purpose. Deaths of infants, torturous illnesses, and forms of agony that end only in the victim’s destruction all fall into these categories. These cases are not logically incompatible with God’s existence, but many argue that they make a loving God exceedingly unlikely.
Yet once that improbability is granted, a further and deeper claim becomes available. It begins from a principle that many theistic traditions themselves affirm: a perfectly loving God would not reasonably permit the world to be structured in such a way that the most rational conclusion for thoughtful, morally serious human beings is that God probably does not exist. On a standard theistic understanding, God desires humans to love, trust, and respond to Him. A loving God would not fill creation with overwhelming evidence pointing the other way. But the existence of vast, gratuitous-seeming suffering appears to do exactly this: it leads sincere and responsible thinkers to conclude that God is improbable. If that is the case, the problem is no longer merely evidential. It becomes logically inconsistent with the idea of a perfectly loving deity who does not deceive or mislead.
This reasoning does not illegitimately jump from “improbable” to “impossible.” Instead, it rests on the claim that for a perfectly loving God, allowing the world to strongly suggest His nonexistence would itself violate divine love. Thus the evidential situation—once evaluated in light of the nature of perfect love—generates a contradiction. The reasoning becomes: if God is perfectly loving, He would not allow the world to look as though He does not exist; yet the world does look that way; therefore, a perfectly loving God does not exist. What begins as an evidential argument thereby yields a logical one.
From this perspective, the difference between saying “God is improbable” and “God does not exist” shrinks significantly. If God existed, He would not want us to believe that He is improbable. The fact that the world makes God’s existence appear unlikely can therefore be taken as decisive evidence that no perfectly loving God stands behind it. In this sense, the evidential argument can be “ditched,” as some say, in favor of a strictly logical argument—yet the practical conclusions change very little. The evidential argument explains why belief in God is unreasonable; the logical argument explains why God cannot exist given the evidential situation. One leads naturally into the other.
Interestingly, the reverse is also true. The logical problem of evil, which insists that evil outright refutes God, still depends on real-world observations. Its claim that any evil would contradict God’s existence implicitly treats each instance of suffering as a piece of evidence that no loving God exists. Thus even the logical argument is evidential in the sense that it relies on what we see and experience in the world. The boundary between the two arguments is therefore porous: evidence feeds the logic, and logic interprets the evidence.
In conclusion, the evidential argument from evil is more powerful than often acknowledged. Properly understood, it does not merely make God’s existence improbable; it provides the foundation for a logical argument that a perfectly loving God cannot exist. By allowing extreme, purposeless, and misleading suffering, the world appears inconsistent with divine love. Once this point is accepted, the evidential argument becomes inseparable from a logical one, and the distinction between them nearly disappears.