The Epicurean paradox points out the contradiction between the existence of evil in the world and the supposed existence of a god who is omniscient (all-knowing), omnipotent (all-powerful), omnibenevolent (all-loving), and omnipresent (present everywhere). The Epicurean Paradox is one formulation of the problem of evil.
Most of the world’s monotheistic religions (e.g., Islam, Judaism, Christianity) describe their gods as having the four attributes described above. This is generally known as classical theism.
As for what philosophers mean by “evil,” it is just a general term of art to describe things we consider to be really bad. In moral philosophy, evil is separated into two general categories: moral and natural.
Examples of moral evil are torture and murder — some very salient examples would be the various acts of mass murder and genocide that have occurred throughout human history. Examples of natural evil would be things like earthquakes, tsunamis, pandemics, famines, etc. — which are capable of killing hundreds of thousands or millions of people over a short span of time. Natural evil also includes the more banal, but still horrible facts of reality (e.g., that we all die and suffer; that many animals are forced to kill other animals to survive; the sheer fact that parasites, predators, and pathogenic organisms exist).
The Epicurean Paradox points out that we would expect the world to be very different from the way it is if a god having these 4 traits were the designer. The fact that the world is the way it is presents a paradox to the traditional religious believer.
Here is how the Epicurean Paradox puts the problem:
“God, [Epicurus] says, either wishes to take away evils, and is unable; or He is able, and is unwilling; or He is neither willing nor able, or He is both willing and able. If He is willing and is unable, He is feeble, which is not in accordance with the character of God; if He is able and unwilling, He is envious, which is equally at variance with God; if He is neither willing nor able, He is both envious and feeble, and therefore not God; if He is both willing and able, which alone is suitable to God, from what source then are evils? Or why does He not remove them?”
(Note: The Epicurean Paradox is named after its purported originator, the ancient Greek philosopher Epicurus; however, this authorship is unconfirmed. The paradox is not found in any existing copies of Epicurus’ works, though many of Epicurus’ works have been lost — including an extensive work about his views on theism. Notably, the passage above is preserved through the Christian writer Lactantius, who attributed it to Epicurus while arguing against it — a fact that adds an ironic dimension to its survival.)
Every classical theistic religion facing this problem has some explanation for the existence of evil in the world. A justification of evil is referred to as a theodicy (theos = god; dikē = justice). A theodicy is essentially a defense of the classical theist’s conception of god. There are many theodicies employed by classical theists, however, none of these are widely seen to be satisfactory by the skeptical.
For example, Christians usually say that God did not bring evil into the world, rather, they say that it was man that brought evil into the world. The story goes something like this: God gave man free will, he misused it, and evil is the result.
This explanation has some pretty clear problems. For one, why did God create a world where the existence of evil is a possibility? He could have created the world however he wanted if he is all powerful. For instance, one could ask, “why give man free will?” Surely an all-powerful God could create a being that didn’t have free will, but was still happy / fulfilled (this is not a logical contradiction). Alternatively, he could have created beings with free will, but placed them in a universe where sin was impossible.
Moreover, the free will defense fails entirely when confronted with natural evil. Human free will cannot account for earthquakes, tsunamis, childhood cancer, or the existence of parasites that blind and kill millions. These horrors exist entirely independently of human choice, and no appeal to free will can explain why an omnibenevolent, omnipotent God would permit — let alone design — a natural world so indifferent to suffering.
There are plenty of other holes to poke in the traditional Christian explanation of evil, but apologists will likely respond that it doesn’t really matter if there is evil in this world, because this world is only temporary — God has offered us a way out of evil and suffering through accepting Jesus as our savior. We are told that if we accept Jesus, we will go to Heaven and there will be no evil there; but part of this story is that there is another place where we will go if we don’t accept Jesus — Hell. Hell, according to the traditional or popular interpretation, is said to be a place of eternal torment. In some versions of the Bible it is described as a “lake of fire,” where there will be unimaginable suffering for those sent there — suffering that will last forever.
So, even if we grant that there is some way for the classical theist to resolve the Epicurean Paradox, there is an even bigger aspect of the problem of evil for their beliefs: the problem of Hell.
Why would an omniscient, omnipotent, omnipresent and omnibenevolent god create a place of eternal torment? Why would this god create a certain individual, knowing (remember, omniscience entails knowing everything, both past, present, and future) that this person will spend an eternity in Hell? Why wouldn’t such a god just not create any person that will end up in Hell? Why create Hell in the first place, or why not just send everyone to Heaven from the start? Ultimately, we must ask why would such a god create anything at all, if even one person has to be subjected to eternal torment? Wouldn’t a universe devoid of conscious experience (besides God’s) be preferable to one in which any conscious beings experience infinite suffering? None of these questions can be satisfactorily answered by traditional religious believers.
It is worth noting that some theologians attempt to soften this problem by reinterpreting Hell not as a place of active eternal torment, but as annihilation — the simple cessation of existence — or as a state of self-chosen separation from God. These reinterpretations, however, fare little better. A god who creates beings he knows will choose annihilation or permanent alienation from all goodness remains difficult to reconcile with omnibenevolence. The problem does not dissolve — it merely changes shape.
So, the Epicurean Paradox, with the Problem of Hell taken into consideration, points out that the typical religious conception of god presents an apparently irresolvable contradiction. Theologians and religious apologists have proposed various solutions to this paradox, however, none of them appear to withstand serious scrutiny.