The Problem of Evil

William Lane Craig

Examines both the logical and probabilistic arguments against God from suffering and evil.

The problem of evil is certainly the greatest obstacle to belief in the existence of God. When I ponder both the extent and depth of suffering in the world, whether due to man’s inhumanity to man or to natural disasters, then I must confess that I find it hard to believe that God exists. No doubt many of you have felt the same way. Perhaps we should all become atheists.

But that’s a pretty big step to take. How can we be sure that God does not exist? Perhaps there’s a reason why God permits all the evil in the world. Perhaps it somehow all fits into the grand scheme of things, which we can only dimly discern, if at all. How do we know?

As a Christian theist, I’m persuaded that the problem of evil, terrible as it is, does not in the end constitute a disproof of the existence of God. On the contrary, in fact, I think that Christian theism is man’s last best hope of solving the problem of evil.

In order to explain why I feel this way, it will be helpful to draw some distinctions to keep our thinking clear. First, we must distinguish between the intellectual problem of evil and the emotional problem of evil. The intellectual problem of evil concerns how to give a rational explanation of how God and evil can co-exist. The emotional problem of evil concerns how to dissolve people’s emotional dislike of a God who would permit suffering.

Now let’s look first at the intellectual problem of evil. There are two versions of this problem: first, the logical problem of evil, and second, the probabilistic problem of evil.

According to the logical problem of evil, it is logically impossible for God and evil to co-exist. If God exists, then evil cannot exist. If evil exists, then God cannot exist. Since evil exists, it follows that God does not exist.

But the problem with this argument is that there’s no reason to think that God and evil are logically incompatible. There’s no explicit contradiction between them. But if the atheist means there’s some implicit contradiction between God and evil, then he must be assuming some hidden premises which bring out this implicit contradiction. But the problem is that no philosopher has ever been able to identify such premises. Therefore, the logical problem of evil fails to prove any inconsistency between God and evil.

But more than that: we can actually prove that God and evil are logically consistent. You see, the atheist presupposes that God cannot have morally sufficient reasons for permitting the evil in the world. But this assumption is not necessarily true. So long as it is even possible that God has morally sufficient reasons for permitting evil, it follows that God and evil are logically consistent. And, certainly, this does seem at least logically possible. Therefore, I’m very pleased to be able to report that it is widely agreed among contemporary philosophers that the logical problem of evil has been dissolved. The co-existence of God and evil is logically possible.

But we’re not out of the woods yet. For now we confront the probabilistic problem of evil. According to this version of the problem, the co-existence of God and evil is logically possible, but nevertheless it’s highly improbable. The extent and depth of evil in the world is so great that it’s improbable that God could have morally sufficient reasons for permitting it. Therefore, given the evil in the world, it’s improbable that God exists.

Now this is a much more powerful argument, and therefore I want to focus our attention on it. In response to this version of the problem of evil, I want to make three main points:

1. We are not in a good position to assess the probability of whether God has morally sufficient reasons for the evils that occur. As finite persons, we are limited in time, space, intelligence, and insight. But the transcendent and sovereign God sees the end from the beginning and providentially orders history so that His purposes are ultimately achieved through human free decisions. In order to achieve His ends, God may have to put up with certain evils along the way. Evils which appear pointless to us within our limited framework may be seen to have been justly permitted within God’s wider framework. To borrow an illustration from a developing field of science, Chaos Theory, scientists have discovered that certain macroscopic systems, for example, weather systems or insect populations, are extraordinarily sensitive to the tiniest perturbations. A butterfly fluttering on a branch in West Africa may set in motion forces which would eventually issue in a hurricane over the Atlantic Ocean. Yet it is impossible in principle for anyone observing that butterfly palpitating on a branch to predict such an outcome. The brutal murder of an innocent man or a child’s dying of leukemia could produce a sort of ripple effect through history such that God’s morally sufficient reason for permitting it might not emerge until centuries later and perhaps in another land. When you think of God’s providence over the whole of history, I think you can see how hopeless it is for limited observers to speculate on the probability that God could have a morally sufficient reason for permitting a certain evil. We’re just not in a good position to assess such probabilities.

2. The Christian faith entails doctrines that increase the probability of the co-existence of God and evil. In so doing, these doctrines decrease any improbability of God’s existence thought to issue from the existence of evil. What are some of these doctrines? Let me mention four:

a. The chief purpose of life is not happiness, but the knowledge of God. One reason that the problem of evil seems so puzzling is that we tend to think that if God exists, then His goal for human life is happiness in this world. God’s role is to provide comfortable environment for His human pets. But on the Christian view this is false. We are not God’s pets, and man’s end is not happiness in this world, but the knowledge of God, which will ultimately bring true and everlasting human fulfillment. Many evils occur in life which maybe utterly pointless with respect to the goal of producing human happiness in this world, but they may not be unjustified with respect to producing the knowledge of God. Innocent human suffering provides an occasion for deeper dependency and trust in God, either on the part of the sufferer or those around him. Of course, whether God's purpose is achieved through our suffering will depend on our response. Do we respond with anger and bitterness toward God, or do we turn to Him in faith for strength to endure?

b. Mankind is in a state of rebellion against God and His purpose. Rather than submit to and worship God, people rebel against God and go their own way and so find themselves alienated from God, morally guilty before Him, and groping in spiritual darkness, pursuing false gods of their own making. The terrible human evils in the world are testimony to man’s depravity in this state of spiritual alienation from God. The Christian is not surprised at the human evil in the world; on the contrary, he expects it. The Bible says that God has given mankind over to the sin it has chosen; He does not interfere to stop it, but lets human depravity run its course. This only serves to heighten mankind’s moral responsibility before God, as well as our wickedness and our need of forgiveness and moral cleansing.

c. The knowledge of God spills over into eternal life. In the Christian view, this life is not all there is. Jesus promised eternal life to all who place their trust in him as their Savior and Lord. In the afterlife God will reward those who have borne their suffering in courage and trust with an eternal life of unspeakable joy. The apostle Paul, who wrote much of the New Testament, lived a life of incredible suffering. Yet he wrote, “We do not lose heart. For this slight, momentary affliction is preparing us for an eternal weight of glory beyond all comparison, because we look not to the things that are seen, but to the things that are unseen, for the things that are seen are transient, but the things that are unseen are eternal” (II Cor. 4:16-18). Paul imagines a scale, as it were, in which all the sufferings of this life are placed on one side, while on the other side is placed the glory that God will bestow on his children in heaven. The weight of glory is so great that it is literally beyond comparison with the suffering. Moreover, the longer we spend in eternity the more the sufferings of this life shrink toward an infinitesimal moment. That’s why Paul could call them “a slight and momentary affliction”—they were simply overwhelmed by the ocean of divine eternity and joy which God lavishes on those who trust Him.

d. The knowledge of God is an incommensurable good. To know God, the source of infinite goodness and love, is an incomparable good, the fulfillment of human existence. The sufferings of this life cannot even be compared to it. Thus, the person who knows God, no matter what he suffers, no matter how awful his pain, can still say, “God is good to me,” simply by virtue of the fact that he knows God, an incomparable good.

These four Christian doctrines greatly reduce any improbability which evil would seem to throw on the existence of God.

3. Relative to the full scope of the evidence, God’s existence is probable. Probabilities are relative to what background information you consider. For example, suppose Joe is a student at the University of Colorado. Now suppose that we are informed that 95% of University of Colorado students ski. Relative to this information it is highly probable that Joe skis. But then suppose we also learn that Joe is an amputee and that 95% of amputees at the University of Colorado do not ski. Suddenly the probability of Joe’s being a skier has diminished drastically!

Similarly, if all you consider for background information is the evil in the world, then it’s hardly surprising that God’s existence appears improbable relative to that. But that’s not the real question. The real question is whether God’s existence is improbable relative to the total evidence available. I’m persuaded that when you consider the total evidence, then God’s existence is quite probable.

Let me mention three pieces of evidence:

a. God provides the best explanation of why the universe exists instead of nothing. Have you ever asked yourself why anything at all exists? Where it all came from ? Typically, atheists have said that the universe is eternal and uncased. But discoveries in astronomy and astrophysics during the last 80 years have rendered this improbable. According to the Big Bang model of the universe, all matter and energy, indeed, physical space and time themselves, came into being at a point about 13.5 billion years ago. Prior to that point, the universe simply did not exist. Therefore, the Big Bang model requires the creation of the universe from nothing.

Now this tends to be very embarrassing for the atheist. Quentin Smith, an atheist philosopher, writes,

The response of atheists and agnostics to this development has been comparatively weak, indeed almost invisible. An uncomfortable silence seems to be the rule when the issue arises among non-believers . . . . The reason for the embarrassment of non-theists is not hard to find. Anthony Kenny suggests it in this statement: ‘A proponent of [the Big Bang] theory, at least if he is an atheist, must believe that the matter of the universe came from nothing and by nothing.’

No such difficulty confronts the Christian theist, since the big Bang theory only confirms what he has always believed: that in the beginning God created the universe. Now I put it to you: which is more plausible: that the Christian theist is right or that the universe popped into being uncaused out of nothing?

2. God provides the best explanation of the complex order in the universe. During the last 40 years, scientists have discovered that the existence of intelligent life depends upon a complex and delicate balance of initial conditions given in the big bang itself. We now know that life-prohibiting universes are vastly more probable than any life-permitting universe like ours. How much more probable?

The answer is that the chances that the universe should be life-permitting are so infinitesimal as to be incomprehensible and incalculable. For example, a change in the strength of gravity or of the atomic weak force by only one part in 10100 would have prevented a life-permitting universe. The so-called cosmological constant "lambda" which drives the inflationary expansion of the universe and is responsible for the recently discovered acceleration of the universe’s expansion is fine-tuned to around one part in 10120. Oxford physicist Roger Penrose calculates that the odds of our universe’s special low entropy condition, on which our lives depend, having arisen sheerly by chance is at least as small as about one part in 1010(123). Penrose comments, “I cannot even recall seeing anything else in physics whose accuracy is known to approach, even remotely, a figure like one part in 1010(123). ” There are multiple quantities and constants which must be fine-tuned in this way if the universe is to permit life. And it’s not just each quantity which must be exquisitely fine-tuned; their ratios to one another must be also finely-tuned. So improbability is multiplied by improbability by improbability until our minds are reeling in incomprehensible numbers.

There is no physical reason why these constants and quantities should possess the values they do. The one-time agnostic physicist Paul Davies comments, “Through my scientific work I have come to believe more and more strongly that the physical universe is put together with an ingenuity so astonishing that I cannot accept it merely as a brute fact.” Similarly, Fred Hoyle remarks, “A common sense interpretation of the facts suggests that a super intellect has monkeyed with physics.” Robert Jastrow, the former head of NASA’s Goddard Institute for Space Studies, calls this the most powerful evidence for the existence of God even to come out of science.

The view that Christian theists have always held, that there is an intelligent designer of the universe, seems to make much more sense than the atheistic view that the universe, when it popped into being uncaused out of nothing, just happened to be by chance fine-tuned to an incomprehensible precision for the existence of intelligent life.

3. Objective moral values in the world. If God does not exist, then objective moral values do not exist. Many theists and atheists alike concur on this point. For example, philosopher of science Michael Ruse explains,

Morality is a biological adaptation no less than are hands and feet and teeth. Considered as a rationally justifiable set of claims about an objective something, ethics is illusory. I appreciate that when somebody says ‘Love thy neighbor as thyself,’ they think they are referring above and beyond themselves. Nevertheless, such reference is truly without foundation. Morality is just an aid to survival and reproduction . . . and any deeper meaning is illusory.

Friedrich Nietzsche, the great atheist of the 19th century who proclaimed the death of God, understood that the death of God meant the destruction of all meaning and value in life.

I think that Friedrich Nietzsche was right.

But we must be very careful here. The question here is not: “Must we believe in God in order to live moral lives?” I’m not claiming that we must. Nor is the question: “Can we recognize objective moral values without believing in God?” I think that we can.

Rather the question is: “If God does not exist, do objective moral values exist?” Like Ruse, I don’t see any reason to think that in the absence of God, the herd morality evolved by homo sapiens is objective. After all, if there is no God, then what’s so special about human beings? They’re just accidental by-products of nature which have evolved relatively recently on an infinitesimal speck of dust lost somewhere in a hostile and mindless universe and which are doomed to perish individually and collectively in a relatively short time. On the atheistic view, some action, say, rape, may not be socially advantageous and so in the course of human development has become taboo; but that does absolutely nothing to prove that rape is really wrong. On the atheistic view, there’s nothing really wrong with your raping someone. Thus, without God there is no absolute right and wrong which imposes itself on our conscience.

But the problem is that objective values do exist, and deep down we all know it. There’s no more reason to deny the objective reality of moral values than the objective reality of the physical world. Actions like rape, cruelty, and child abuse aren’t just socially unacceptable behavior—they’re moral abominations. Some things are really wrong.

Thus, paradoxically, evil actually serves to establish the existence of God. For if objective values cannot exist without God and objective values do exist—as is evident from the reality of evil—, then it follows inescapably that God exists. Thus, although evil in one sense calls into question God’s existence, in a more fundamental sense it demonstrates God’s existence, since evil could not exist without God.

These are only part of the evidence that God exists. The prominent philosopher Alvin Plantinga has expounded two dozen or so arguments for God’s existence. The cumulative force of these arguments makes it probable that God exists.

In summary, if my three theses are correct, then evil does not render improbable the existence of the Christian God; on the contrary, considering the full scope of the evidence, God’s existence is probable. Thus, the intellectual problem of evil fails to overthrow God’s existence.

But that takes us to the emotional problem of evil. I think that most people who reject God because of the evil in the world don’t really do so because of intellectual difficulties; rather it’s an emotional problem. They just don’t like a God who would permit them or others to suffer and therefore they want nothing to do with Him. Theirs is simply an atheism of rejection. Does the Christian faith have something to say to these people?

It certainly does! For it tells us that God is not a distant Creator or impersonal ground of being, but a loving Father who shares our sufferings and hurts with us. Prof. Plantinga has written,

As the Christian sees things, God does not stand idly by, coolly observing the suffering of His creatures. He enters into and shares our suffering. He endures the anguish of seeing his son, the second person of the Trinity, consigned to the bitterly cruel and shameful death of the cross. Christ was prepared to endure the agonies of hell itself . . . in order to overcome sin, and death, and the evils that afflict our world, and to confer on us a life more glorious that we can imagine. He was prepared to suffer on our behalf, to accept suffering of which we can form no conception.

You see, Jesus endured a suffering beyond all comprehension: He bore the punishment for the sins of the whole world. None of us can comprehend that suffering. Though He was innocent, He voluntarily took upon himself the punishment that we deserved. And why? Because He loves us. How can we reject Him who gave up everything for us?

When we comprehend His sacrifice and His love for us, this puts the problem of evil in an entirely different perspective. For now we see clearly that the true problem of evil is the problem of our evil. Filled with sin and morally guilty before God, the question we face is not how God can justify Himself to us, but how we can be justified before Him.

So paradoxically, even though the problem of evil is the greatest objection to the existence of God, at the end of the day God is the only solution to the problem of evil. If God does not exist, then we are lost without hope in a life filled with gratuitous and unredeemed suffering. God is the final answer to the problem of evil, for He redeems us from evil and takes us into the everlasting joy of an incommensurable good, fellowship with Himself.