''There is nothing that an omnipotent God could not do.' 'No.' 'Then, can God do evil?' 'No.' 'So that evil is nothing, since that is what He cannot do who can do anything.'
Anicius Manlius Severinus Boethius (480? - 524?), Roman philosopher and statesman, The Consolation of Philosophy
"An implication of intelligent design may be that the designer is benevolent and, as such, the constants and structures of the universe are 'life-friendly'. However such intelligent designer may conceivably be malevolent . (I)t is reasonable to conclude that God does not exist, since God is omnipotent, omniscient and perfectly good and thereby would not permit any gratuitous natural evil. But since gratuitous natural evils are precisely what we would expect if a malevolent spirit created the universe . If any spirit created the universe, it is malevolent, not benevolent."
Quentin Smith, The Anthropic Coincidences, Evil and the Disconfirmation of Theism
Nequaquam nobis divinitus esse creatum
Naturam mundi, quĉ tanta est prĉdita culpa.
Lucretius (De Rerum Natura)
I. The Logical Problem of Evil
God is omniscient, omnipotent and good (we do not discuss here more "limited" versions of a divine Designer or Creator). Why, therefore won't he eliminate Evil? If he cannot do so, then he is not all-powerful (or not all-knowing). If he will not do so, then surely he is not good! Epicurus is said to have been the first to offer this simplistic formulation of the Logical (a-priori, deductive) Problem of Evil, later expounded on by David Hume in his "Dialogues Concerning Natural Religion" (1779).
Evil is a value judgment, a plainly human, culture-bound, period-specific construct. St. Thomas Aquinas called it "ens rationis", the subjective perception of relationships between objects and persons, or persons and persons. Some religions (Hinduism, Christian Science) shrug it off as an illusion, the outcome of our intellectual limitations and our mortality. As St. Augustine explained in his seminal "The City of God" (5th century AD), what to us appears heinous and atrocious may merely be an integral part of a long-term divine plan whose aim is to preponderate good. Leibniz postulated in his Theodicy (1710) that Evil (moral, physical, and metaphysical) is an inevitable part of the best logically possible world, a cosmos of plenitude and the greatest possible number of "compatible perfections".
But, what about acts such as murder or rape (at least in peace time)? What about "horrendous evil" (coined by Marilyn Adams to refer to unspeakable horrors)? There is no belief system that condones them. They are universally considered to be evil. It is hard to come up with a moral calculus that would justify them, no matter how broad the temporal and spatial frame of reference and how many degrees of freedom we allow.
The Augustinian etiology of evil (that it is the outcome of bad choices by creatures endowed with a free will) is of little help. It fails to explain why would a sentient, sapient being, fully aware of the consequences of his actions and their adverse impacts on himself and on others, choose evil? When misdeeds are aligned with the furtherance of one's self-interest, evil, narrowly considered, appears to be a rational choice. But, as William Rowe observed, many gratuitously wicked acts are self-defeating, self-destructive, irrational, and purposeless. They do not give rise to any good, nor do they prevent a greater evil. They increase the sum of misery in the world.
As Alvin Plantinga suggested (1974, 1977) and Bardesanes and St. Thomas Aquinas centuries before him, Evil may be an inevitable (and tolerated) by-product of free will. God has made Himself absent from a human volition that is free, non-deterministic, and non-determined. This divine withdrawal is the process known as "self-limitation", or, as the Kabbalah calls it: tsimtsum, minimization. Where there's no God, the door to Evil is wide open. God, therefore, can be perceived as having absconded and having let Evil in so as to facilitate Man's ability to make truly free choices. It can even be argued that God inflicts pain and ignores (if not leverages) Evil in order to engender growth, learning, and maturation. It is a God not of indifference (as proposed by theologians and philosophers from Lactantius to Paul Draper), but of "tough love". Isaiah puts it plainly: "I make peace and create evil" (45:7).
Back to the issue of Free Will.
The ability to choose between options is the hallmark of intelligence. The entire edifice of human civilization rests on the assumption that people's decisions unerringly express and reflect their unique set of preferences, needs, priorities, and wishes. Our individuality is inextricably intermeshed with our ability not to act predictably and not to succumb to peer pressure or group dynamics. The capacity to choose Evil is what makes us human.
Things are different with natural evil: disasters, diseases, premature death. These have very little to do with human choices and human agency, unless we accept Richard Swinburne's anthropocentric - or, should I say: Anthropic? - belief that they are meant to foster virtuous behaviors, teach survival skills, and enhance positive human traits, including the propensity for a spiritual bond with God and "soul-making" (a belief shared by the Mu'tazili school of Islam and by theologians from Irenaeus of Lyons and St. Basil to John Hick).
Natural calamities are not the results of free will. Why would a benevolent God allow them to happen?
Because Nature sports its own version of "free will" (indeterminacy). As Leibniz and Malebranche noted, the Laws of Nature are pretty simple. Not so their permutations and combinations. Unforeseeable, emergent complexity characterizes a myriad beneficial natural phenomena and makes them possible. The degrees of freedom inherent in all advantageous natural processes come with a price tag: catastrophes (Reichenbach). Genetic mutations drive biological evolution, but also give rise to cancer. Plate tectonics yielded our continents and biodiversity, but often lead to fatal earthquakes and tsunamis. Physical evil is the price we pay for a smoothly-functioning and a fine-tuned universe.
II. The Evidential Problem of Evil
Some philosophers (for instance, William Rowe and Paul Draper) suggested that the preponderance of (specific, horrific, gratuitous types of) Evil does not necessarily render God logically impossible (in other words, that the Problem of Evil is not a logical problem), merely highly unlikely. This is known as the Evidential or Probabilistic (a-posteriori, inductive) Problem of Evil.
As opposed to the logical version of the Problem of Evil, the evidential variant relies on our (fallible and limited) judgment. It goes like this: upon deep reflection, we, human beings, cannot find a good reason for God to tolerate and to not act against intrinsic Evil (i.e. gratuitous evil that can be prevented without either vanquishing some greater good or permitting some evil equally bad or worse). Since intrinsic evil abounds, it is highly unlikely that He exists.
Skeptic Theists counter by deriding such thinkers: How can we, with our finite intellect ever hope to grasp God's motives and plan, His reasons for action and inaction? To attempt to explicate and justify God (theodicy) is not only blasphemous, it is also presumptuous, futile, and, in all likelihood, wrong, leading to fallacies and falsities.
Yet, even if our intelligence were perfect and omniscient, it would not necessarily have been identical to or coextensive with God's. As we well know from experience, multiple intelligences with the same attributes often obtain completely different behaviors and traits. Two omniscient intellects can reach diametrically-opposed conclusions, even given the same set of data.
We can turn the evidential argument from evil on its head and, following Swinburne, paraphrase Rowe:
If there is an omnipotent and omniscient being, then there are specific cases of such a being's intentionally allowing evil occurrences that have wrongmaking properties such that there are rightmaking characteristics that it is reasonable to believe exist (or unreasonable to believe do not exist) and that both apply to the cases in question and are sufficiently serious to counterbalance the relevant wrongmaking characteristics.
Therefore it is likely that (here comes the inductive leap from theodicy to defense):
If there is an omnipotent and omniscient being, then there is the case of such a being intentionally allowing specific or even all evil occurrences that have wrongmaking properties such that there are rightmaking characteristics that it is reasonable to believe exist (or unreasonable to believe do not exist) - including ones that we are not aware of - that both apply to the cases in question, or to all Evil and are sufficiently serious to counterbalance the relevant wrongmaking characteristics.
Back to reality: given our limitations, what to us may appear evil and gratuitous, He may regard as necessary and even beneficial (Alston, Wykstra, Plantinga).
Even worse: we cannot fathom God's mind because we cannot fathom any mind other than our own. This doubly applies to God, whose mind is infinite and omniscient: if He does exist, His mind is alien and inaccessible to us. There is no possible intersubjectivity between God and ourselves. We cannot empathize with Him. God and Man have no common ground or language. It is not Hick's "epistemic distance", which can be bridged by learning to love God and worship Him. Rather, it is an unbridgeable chasm.
This inaccessibility may cut both ways. Open Theists (harking back to the Socinians in the 17th century) say that God cannot predict our moves. Deists say that He doesn't care to: having created the Universe, He has moved on, leaving the world and its inhabitants to their own devices. Perhaps He doesn't care about us because He cannot possibly know what it is to be human, He does not feel our pain, and is incapable of empathizing with us. But this view of an indifferent God negates his imputed benevolence and omnipotence.
This raises two questions:
(i) If His mind is inaccessible to us, how could we positively know anything about Him? The answer is that maybe we don't. Maybe our knowledge about God actually pertains to someone else. The Gnostics said that we are praying to the wrong divinity: the entity that created the Universe is the Demiurge, not God.
(ii) If our minds are inaccessible to Him, how does He make Himself known to us? Again, the answer may well be that He does not and that all our "knowledge" is sheer confabulation. This would explain the fact that what we think we know about God doesn't sit well with the plenitude of wickedness around us and with nature's brutality.
Be that as it may, we seem to have come back full circle to the issue of free will. God cannot foresee our choices, decisions, and behaviors because He has made us libertarian free moral agents. We are out of His control and determination and, thus, out of His comprehension. We can choose Evil and there is little He can do about it.
III. Aseity and Evil
Both formulations of the Problem of Evil assume, sotto voce, that God maintains an intimate relationship with His creation, or even that the essence of God would have been different without the World. This runs contra to the divine attribute of aseity which states flatly that God is self-sufficient and does not depend for His existence, attributes, or functioning on any thing outside Himself. God, therefore, by definition, cannot be concerned with the cosmos and with any of its characteristics, including the manifestations of good and evil. Moreover, the principle of aseity, taken to its logical conclusion, implies that God does not interact with the World and does not change it. This means that God cannot or will not either prevent Evil or bring it about.
IV. God as a Malicious Being
A universe that gives rise to gratuitous Evil may indicate the existence of an omnipotent, omniscient, but also supremely malevolent creator. Again, turning on its head the familiar consequentialist attempt to refute the evidential argument from evil, we get (quoting from the Stanford Encyclopedia of Philosophy's article about The Problem of Evil):
"(1) An action is, by definition, morally right if and only if it is, among the actions that one could have performed, an action that produces at least as much value as every alternative action;
(2) An action is morally wrong if and only if it is not morally right;
(3) If one is an omnipotent and omniscient being, then for any action whatever, there is always some (alternative) action that produces greater value."
In other words, the actions of an omnipotent and omniscient being are always morally wrong and never morally right. This is because among the actions that such a being could have performed (instead of the action that he did perform) there is an infinity of alternatives that produce greater value.
Moreover, an omnibenevolent, merciful, and just God is hardly likely to have instituted an infinite Hell for nonbelievers. This is more in tune with a wicked, vicious divinity. To suggest the Hell is the sinner's personal choice not to be with God (i.e. to sin and to renounce His grace) doesn't solve the problem: for why would a being such as God allow mere ignorant defective mortals a choice that may lead them straight to Hell? Why doesn't He protect them from the terrifying outcomes of their nescience and imperfection? And what kind of "choice" is it, anyway? Believe in me, or else ... (burn in Hell, or be annihilated).
V. Mankind Usurping God - or Fulfilling His Plan?
A morally perfect God (and even a morally imperfect one) would surely wish to minimize certain, horrendous types of gratuitous Evil albeit without sacrificing the greater good and while forestalling even greater evils. How can God achieve these admirable and "ego"-syntonic goals without micromanaging the World and without ridding it of the twin gifts of free will and indeterminacy?
If there is a God, He may have placed us on this Earth to function as "moral policeman". It may be our role to fight Evil and to do our best to eradicate it (this is the view of the Kabbalah and, to some extent, Hegel). We are God's rightmaking agents, his long arm, and his extension. Gradually, Mankind acquires abilities hitherto regarded as the exclusive domain of God. We can cure diseases; eliminate pain; overcome poverty; extend life, fight crime, do justice. In the not too distant future we are likely to be able to retard ageing; ameliorate natural catastrophes; eradicate delinquency (remember the film "Clockwork Orange"?).
Imagine a future world in which, due to human ingenuity and efforts, Evil is no more. Will free will vanish with it and become a relic of a long-forgotten past? Will we lose our incentive and capacity to learn, improve, develop, and grow? Will we perish of "too much good" as in H. G. Wells' dystopia "The Time Machine"? Why is it that God tolerates Evil and we seek to dispose of it? In trying to resist Evil and limit it, are we acting against the Divine Plan, or in full compliance with it? Are we risking His wrath every time we temper with Nature and counter our propensity for wickedness, or is this precisely what He has in store for us and why He made us?
Many of these questions resolve as if by magic once we hold God to be merely a psychological construct, a cultural artifact, and an invention. The new science of neuro-religion traces faith to specific genes and neurons. Indeed, God strikes some as a glorified psychological defense mechanism: intended to fend off intimations of a Universe that is random, meaningless and, ipso facto, profoundly unjust by human criteria. By limiting God's omnipotence (since He is not capable of Evil thoughts or deeds) even as we trumpet ours (in the libertarian view of free will), we have rendered His creation less threatening and the world more habitable and welcoming. If He is up there, He may be smiling upon our accomplishments against all odds.