The Problem of Evil

A Lecture at Dartmouth College on February 2, 1998



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Evil is all pervasive. Everywhere we go, everywhere we look, we are faced with evil in a variety of forms. Not only do we see it with our own eyes as we walk the streets of our city or our campus, but television, radio and the newspapers thrust the reality of evil in our faces everyday.

Evil is a problem for thinking people. We want to understand it, explain it and make sense of our lives in light of it. When we step back to take a look at evil, we see that it is very hard to define. So I should say something about what I mean when I use the word “evil.” I take the term “evil” to cover the whole variety of bad things that happen. Everything from the great atrocities such as AIDS and the Holocaust to the less cosmic sufferings such as loneliness. I would take physical pains and relational problems as counting as evil as well.

What philosophers call “the problem of evil” is really a family of arguments. These are arguments from the existence or nature of evil to the conclusion that God does not or probably does not exist.

The problem of evil has been one of the greatest objections to theism since theism has been around. If it is not the greatest philosophical problem with theism, it is at least the problem with the greatest emotional impact. Everywhere and in every age sensitive thinkers have been confronted with the magnitude of evil in the world, both moral and natural, and have asked the question, “Why?”

If God is all powerful and all loving why does He not eliminate evil? The existence of evil is seen as proof or evidence that there is no all powerful, all loving God.

Before we get into approaching an answer to this problem we must understand what questions are being asked.


Defining the Problem

The Deductive Problem – The Key Word: Incompatibility
The deductive problem is the claim that there is a logical contradiction in asserting that God is all powerful, God is all loving and that evil exists. Wouldn’t this kind of God eliminate all evil? The existence of God, on this view, is on a par with a square circle. Given the existence of evil, it is impossible for God to exist. The challenge is to show that theism is logically consistent.

The Evidential Problem – The Key Word: Evidence
The Evidential Problem admits that the existence of God and the reality of evil are not logically incompatible but the amount and the kinds of evil we find in the world is strong evidence against the existence of an all-loving all-powerful God. Therefore the existence of God is improbable.

The Deductive Problem

What is the Deductive Problem?
The deductive problem of evil claims that the following two statements are logically inconsistent. I am following the work of John Mackie, Oxford Professor of Philosophy in his paper “Evil and Omnipotence” (Mind, 1955).

1. God exists and is wholly good, omnipotent and omniscient.
2. Evil exists.

If these are logically inconsistent, they cannot both be true. Given that it is obvious that evil exists, God cannot exist.

Deriving the Contradiction
If there is a contradiction between these statements, it is not immediately evident. In order to show that these are inconsistent, we must derive an explicit contradiction from them. We can do this by adding two premises.

3. There are no limits to what an omnipotent, omniscient being can do.
4. A good being always eliminates evil as far as it can.

From these we can proceed in easy steps:
5. (If 1 and 4 are true) God eliminates all of the evil He can eliminate — because He is good.
6. (If 1 and 3 are true) God can eliminate all of the evil there is — because He is powerful enough.

7. (If 5 and 6 are true) God eliminates all evil.

8. (If 7 is true) There is no evil.

9. (But from 2 and 8) There is evil and there is no evil.

This is the contradiction. What this means is that one of our assumptions is false. Since it is obvious that there is evil, 2. is true. Therefore, 1. must be false. There is no God.

Mackie, then has succeeded in deriving a contradiction from two claims theists make with the help of two additional premises. Has he proven that there is no God?

Answering the Deductive Problem
What will a theist say about this argument? First, a theist will not deny that evil exists. Second, a theist will not deny that God exists and is wholly good, omnipotent and omniscient.

What the theist must do is deny one or both of the additional premises Mackie adds to generate the contradiction. Remember they are:

3. There are no limits to what an omnipotent, omniscient being can do.
4. A good being always eliminates evil as far as it can.

Are these true? Actually both of them are false. Let us take them one at a time. Beginning with the nature of omnipotence.

Premise 3
What does it mean that God is all powerful? Can He do anything? Can God make a round square? The answer to the last question is No! God cannot make a round square. The fact that He is all powerful means He can do anything that is not a logical contradiction or a contradiction to His character. A round square is a logical contradiction and a logical impossibility. It is not a genuine possibility. It is really not a thing at all and therefore it is not surprising that God cannot make one.

So there are limits — logical limits — to what an omnipotent being can do.

This is not a trick by the theist. If God could do contradictions, we could not develop an argument against his existence.

Suppose we show that God’s existence and the existence of evil are contradictory. That is no problem for God. It doesn’t mean God cannot exist. God could make them both true. To have an argument against God’s existence we must believe that God cannot do contradictions.

So premise 3. is false in Mackie’s argument. We must revise it:

3* There are no non-logical limits to what an omnipotent being can do.

Premise 4
What about premise 4? Does a good being always eliminate evil as much as it can? The answer is No. A good being can allow evil and still be good IF it has good reason to allow it.

Think of a parent. Suppose I give my son an allowance — which I don’t. Suppose I gave him a dollar a week — which I wouldn’t. Now suppose he takes his dollar and buys bubble gum with it. After a day he has chewed the gum and gotten it stuck in his hair. Now he wants a ball. I don’t buy it for him because I want him to learn how to handle money. Of course he is very upset.

Now I allow a certain evil to occur — his being upset. I could have prevented it by buying the ball for him. Am I not being good? This does not count against my goodness because I have a good reason to allow this evil.

So we must change 4. in order to make it true:

4* A good thing always eliminates evil as far as it can unless it has a good reason to allow the evil.
This has a better chance of being true. But we cannot derive a contradiction from 1. and 2. by using 3* and 4*.

So the theist’s argument goes like this:

1. God exists and is wholly good, omnipotent and omniscient.
2. Evil exists.

3* A good thing always eliminates evil as far as it can unless it has a good reason to allow it.

4* There are no non-logical limits to what an omnipotent being can do.

From this we can derive

8* No evil exists unless God has a good reason to allow it.
This is not a contradiction of 2. So we have shown that there is no contradiction between the existence of God and the existence of evil.

What Reason Could God Have to Allow Evil?
We don’t need to claim that we know why, exactly, God allows evil. We only need a possible reason that shows that the existence of evil is not inconsistent with the existence of God.

One possible reason is to preserve the freedom of the will.

The Nature of Freedom – What does it mean to have free will?
1. Free Moral Agents are able to choose between moral alternatives (good and evil) without being under compulsion to choose one or the other. This is known as a libertarian notion of freedom. If there is any compulsion, then the choice is not free — it is forced. This is the definition of freedom.

2. If God creates Free Moral Agents, they must be able, by definition, to choose evil as well as good. He cannot make us never sin without violating our freedom. A Free Moral Agent who is forced to choose good is a logical impossibility. He is a contradiction. God cannot make a logical impossibility.

3. There are two logical alternatives in creating

(1) Free Moral Agents with the possibility of evil
(2) Determined Non-Moral Non-Agents

Why should God create Free Moral Agents and risk evil?

Most of the things that make life worthwhile require the freedom of the will. For example:

Moral Responsibility
Personal Projects and Accomplishment
If your mother was paying your girlfriend a LOT of money to go out with you…you’d be repulsed. For the relationship to be meaningful, it must be freely chosen.

Now, Free Will is not a sufficient reason for God to allow every kind of evil in the world. For instance, evils we call natural evils which include things like floods and earthquakes are not immediately a result of the misuse of free will. What reason might God have to allow these kinds of evils?

Again, I do not think we can know all the reasons but there are some possible reasons we can know. One possible reason is:

The Regularity of Cause and Effect
In order to make meaningful action possible, it must be possible to affect the world. If we could not make any difference to the world and if we could not predict the affect of our actions, it would be impossible to act meaningfully.

The regularity of cause and effect makes possible our meaningful actions. It also makes possible situations in which the environment causes severe damage to persons. The very reason fire is useful is the reason it burns down houses. The chemical construction of water which makes it vital also makes it possible for us to drown.

The fact that nature operates with causal laws makes possible our biological life. It also makes possible these natural evils. So the regularity of causal laws is a good thing. Perhaps the reason God allows natural evils, then, is the need for causal laws.


The Free-will defense is a good basic answer to the Deductive problem — the charge that evil and the existence of God are contradictory. We haven’t dealt with all cases and all questions but this is a basis for dialogue and a basis for further study.

In fact, even atheist Philosophers do not support this kind of argument any more. William Rowe has written:

Some philosophers have contended that the existence of evil is logically inconsistent with the existence of the theistic God. No one, I think, has succeeded in establishing such an extravagant claim. Indeed, granted incompatibilism, there is a fairly compelling argument for the view that the existence of evil is logically consistent with the existence of the theistic God. (“The Problem of Evil and Some Varieties of Atheism,” APQ 16 (1979) footnote 1, p. 335)

The Evidential Problem
The theistic answer to the deductive problem of evil is based on the claim that it is possible that God has a good reason for all of the evil He allows. If it is possible that God has a sufficient reason, the deductive argument is defeated. The evidential problem of evil takes up a different question. The question is whether it is likely that God has a sufficient reason for the evil we see.

There are cases of intense evil which appear to be completely gratuitous or senseless. Examples of evils which fit this argument are things like animals enduring intense pain in a forest fire, brutal crimes and other horrendous evils. The argument points out that it seems like there is no good reason to allow these cases of evil. These seem to make it impossible or at least improbable that God exists. The basic structure of this type of argument is as follows:

1. If there is unjustified evil (evil which God has no good reason to allow), God does not exist.
2. Probably there is unjustified evil.

3. Therefore, Probably God does not exist.

The second premise is the key premise in understanding this argument. Why should we accept it? How could we possibly know that it is true? The argument for this premise goes as follows:

4. It SEEMS as though God could have no good reason to allow this evil.
5. It is probably true that God has no reason to allow it.

Is this jump justified? Those who find the argument against the existence of God from gratuitous evil compelling believe this jump is justified. I do not. It may be true that I do not know of a good reason to allow a particular evil but that does not mean that there is no reason or that I should believe that there is no reason.

So the argument is that evil for which it seems like there is no good reason is evidence against the existence of God.

Answering the Evidential Problem
The basic theistic responses is to deny that 4 gives us good reason to believe 5. In other words,

4. It SEEMS as though God could have no good reason to allow this evil. does not support

5. It is probably true that God has no good reason to allow it.
Why does a theist think 4 does not support 5? Sometimes this kind of reasoning is good reasoning and sometimes it is not. For example:

6. It seems like there are no elephants in this room does support…

7. There probably are no elephants in this room. But what about…

8. It seems like there are no carbon 14 atoms in this room. This does not support…

9. Probably there are no carbon 14 atoms in this world.
What is the difference?

The difference between elephants and Carbon 14 atoms in this regard can be explained as follows. Consider the sentence:

10. If there were any X’s in the room, we would probably know it.
The sentence is true when it is about elephants and it is false when it is about Carbon 14 atoms. If there were a live elephant in this room we would probably know it.

Now is a good reason God might have for allowing some evil more like an elephant or a carbon 14 atom? Is it more reasonable to believe that I would be able to figure it out if it is there or that I would not be able to figure it out? Is the following true:

11. If God had a reason to allow this particular case of evil, we would probably know what it is.
Since God’s knowledge and wisdom is so far beyond ours, it is eminently reasonable to suppose that He will have reasons which we cannot grasp for allowing evils in our lives. It is not that we cannot figure out some of the reasons God has for some evils. In fact we can figure out at least plausible reasons for most evil. There will still be some evil the reason for which we cannot discern. This is exactly what we should expect if there is a God. It cannot be counted as evidence against God.

So even though it might seem, at first glance, that there are no good reasons to allow certain evils we see, this does not provide strong evidence that these evils are really unjustified. Evil, then, is not strong evidence against the existence of God.

Flipping the Coin

Whenever I discuss the problem of evil, I “flip the coin” and show that the problem of evil is at least as tough of a problem for the non-theist as it is for the theist. Here are a few good questions to consider.

How can a Random Universe allow so Much Good?
This thought was the turning point in my committing my life to Christ at the age of sixteen. I thought that there was too much good in the world for it to have been a cosmic accident. I thought of relationships with friends, the beauty of the natural world etc. and concluded there had to be a Personal source.

How Can We Call Anything Evil if There is no God?
This is by far the most challenging response to the non-theists view of the problem of evil. Dostoevski wrote, “If there is no God, everything is permitted.” The question is , “How can the non-theist justify his moral indignation?” If there is no absolute standard of morality, how can I call racism wrong? To call anything wrong, by the definition of the word, implies that it falls short of a given moral standard. If there is no God, by what standard can we judge actions such as racism and the Holocaust? If we say there is no standard then all we can say about these actions is that we don’t like them or they are inconvenient or that the majority of people probably don’t like them.

Harry Blamires wrote, “Unless we presuppose a good God at the back of the universe, the question ‘Why suffering?’ is on a par with the question ‘Why cabbages?'” Evil is bad, in any absolute sense, only if God exists. If He doesn’t, then evil has no moral weight at all.

Moral evil in the world does not shake my faith in God but it sure shakes (destroys) my faith in Human Nature.
This seems so obvious but people rarely question the prevalent assumption that human nature is morally blameless when they are confronted with evil. God’s nature is so flippantly called into question. All moral evil is directly caused by humans beings. Sometimes I ask someone who states that human nature is innocent, “Do you keep your doors locked? If so, why?” I should ask in this context, “Is it because you think God will rip you off or some person may do it? If you lock your doors to protect yourself from others, why do you blame God and not humans for moral evil?”

God HAS ALREADY defeated evil at its root without violating human freedom!
This is where the primary and central theme of Christianity relates to the problem of evil. God has gotten involved! He has defeated evil and not violated our freedom. The Atonement, in Christian Theology, was the event in history where God Himself, in the person of Jesus Christ, took upon Himself all of the eternal results and penalty of our moral evil. As a result, we can be freed from our just penalty and we can have forgiveness. In addition, by accepting His offer of this forgiveness we are adopted into a relationship with the all loving, all powerful God and He gives us moral power to overcome the evil in our lives.

God WILL IN THE FUTURE defeat evil in its entirety without violating human freedom!
Another central theme in Christian Theology is that God will step again into history and bring it to a close. The promise is that He will judge all people with absolute justice and fairness. Every moral evil will be judged. There will not be one act of exploitation or even unkindness that will escape His notice. When we stand before Him we will know that we have no excuse.

Summary Statements

The existence of evil in the world does not render theism untenable. It is a significant challenge but there is no logical contradiction in believing in an all loving, all powerful God and acknowledging the reality of evil. In fact the nature of evil and our universal judgement of it as evil, creates serious problems for the non-theist. There are many more angles to be explored and research to be done in this issue that touches the lives of every human.

Application to Personal Life

1. Everyone has a philosophy of life — even if it is vague.
2. Every philosophy of life makes exclusive truth claims.
3. If one rejects Christian Theism, one should be able to justify one’s alternative — that is, if one wishes to maintain intellectual integrity.

Greg Ganssle has been thinking about the intersection of Christian faith and contemporary scholarship for over thirty years. He began as an undergraduate by skipping his classes and reading C.S. Lewis. After graduating from the University of Maryland in 1978, he worked in campus ministry on a variety of campuses. Hundreds of conversations with students from a wide variety of religious and philosophical perspectives drove him to a sustained self-study program. Eventually it occurred to him that he was reading philosophy. Since he had escaped college without taking a philosophy course, he decided to begin with Philosophy 101 at the age of 25. Within weeks he was hooked. Continuing to juggle his full time campus ministry responsibilities, he earned a Master of Arts in Philosophy from the University of Rhode Island in 1990. He then went full time and earned his doctorate in philosophy from Syracuse University in 1995, where his dissertation on God’s relation to time won a Syracuse University Dissertation Award. In addition to publishing nearly three dozen articles, chapters and reviews, Greg is also the author of Our Deepest Desires: How the Christian Story Fulfills Human Aspirations (IVP, 2017), Thinking about God: First Steps in Philosophy (IVP, 2004) and A Reasonable God: Engaging the New Face of Atheism (Baylor University Press, 2009). Greg was part-time lecturer in the philosophy department at Yale for nine years and a senior fellow at the Rivendell Institute at Yale. Greg has been married to Jeanie since 1985. They have three children, none of whom are philosophers. Although happily married, Greg has a secret crush on Jane Austen.

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