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Course 8 · Lesson 7.3

The problem of evil: logical and evidential forms

13 minute read

Lessons in this course

Course 8 outline

Module 1: Speaking About God

  1. What systematic theology is and what it can claim
  2. Naming God: analogy, negation and the limits of language
  3. Classical theism defined and compared with alternatives
  4. Beyond the world and present in it: transcendence and immanence

Module 2: The Classical Attributes

  1. Divine simplicity: God is not made of parts
  2. Divine immutability: does God change?
  3. Divine eternity: timeless or everlasting?
  4. Divine omniscience and human freedom

Module 3: The Trinity in Scripture and the Early Church

  1. One God: the Shema and the Old Testament background
  2. Father, Son and Spirit in the New Testament
  3. Early Trinitarian language: Justin, Irenaeus and Tertullian
  4. Two early errors: modalism and subordinationism

Module 4: Arius, Athanasius and Nicaea

  1. What Arius taught and why it spread
  2. The Council of Nicaea in 325 and the word homoousios
  3. The long fight after Nicaea and the role of Athanasius
  4. Constantinople in 381 and the deity of the Holy Spirit

Module 5: The Cappadocians and the Shape of Trinitarian Thought

  1. One ousia, three hypostases: the Cappadocian vocabulary
  2. Basil, Gregory of Nazianzus and Gregory of Nyssa
  3. Augustine and the Western tradition
  4. The filioque and the monarchy of the Father

Module 6: Creation from Nothing

  1. Creation in Scripture
  2. Rivals to creation from nothing: eternal matter and emanation
  3. The doctrine of creation ex nihilo and its development
  4. Creation, the goodness of matter and the Trinity

Module 7: Providence, Sovereignty and Evil

  1. Providence: preservation, concurrence and governance
  2. Divine sovereignty and human freedom across the traditions
  3. The problem of evil: logical and evidential forms
  4. Christian responses: free will, privation and the suffering God
  5. Evaluating the responses and living with what remains unanswered

All courses

Program / Course 8: God, Trinity, and Creation / Lesson 7.3

What you will learn

  • State the problem of evil clearly and fairly, and distinguish the logical from the evidential form.
  • Distinguish moral evil, natural evil and horrendous evil.
  • Describe J. L. Mackie’s argument, Plantinga’s reply, and William Rowe’s evidential argument.
  • Explain why many philosophers think the logical form has failed while the evidential form remains debated.

The big idea

The problem of evil asks how an all-powerful, all-knowing and perfectly good God can exist in a world with so much suffering and wrongdoing. It is the most serious objection to belief in God, and it is also one of the most personal. Philosophers distinguish two forms. The logical form claims that God and evil cannot both exist. The evidential form claims that the amount and kind of evil make God’s existence unlikely. Most philosophers, including many nonbelievers, think the logical form has been answered. The evidential form is still debated.

Key terms

Problem of evil
The challenge to belief in God from the existence of evil and suffering.
Moral evil
Evil caused by the free choices of persons, such as cruelty and injustice.
Natural evil
Suffering that comes from nature without human choice, such as disease, earthquakes and famine.
Logical problem of evil
The claim that it is logically impossible for God and evil to exist together.
Evidential problem of evil
The claim that evil, while not strictly incompatible with God, makes God’s existence improbable.
Theodicy
From Greek for justifying God. An attempt to explain why God allows evil. Coined by Leibniz.
Defense
A response which shows that evil and God are not contradictory without claiming to know God’s actual reasons.
Horrendous evil
A term from Marilyn McCord Adams for evils so deep that they threaten to make a person’s life not worth living.

Background

The problem is ancient. A set of questions attributed in later sources to the Greek philosopher Epicurus asks whether God is willing to prevent evil but not able, or able but not willing, or neither, or both. The ancient source for the exact wording is uncertain, and it is preserved in the Christian writer Lactantius. David Hume put the argument in memorable form in the Dialogues Concerning Natural Religion in 1779. The Bible does not argue the problem abstractly. It brings it forward as a cry, in the Psalms of lament, in Job and Ecclesiastes, and in the prophets.

In modern philosophy the discussion became more precise in the twentieth century. J. L. Mackie, in an essay of 1955 titled Evil and Omnipotence, argued that the claims that God is all-powerful, that God is perfectly good and that evil exists are inconsistent. Alvin Plantinga answered in the 1960s and 1970s with the free will defense, and by the 1980s many philosophers, including Mackie’s followers, granted that the strict logical contradiction had not been shown. William Rowe then proposed in 1979 the evidential form.

Alongside these philosophical debates there have been other, more personal ones. Dostoevsky’s Ivan Karamazov refuses to accept a harmony purchased with a child’s tears. Marilyn McCord Adams, a philosopher and Anglican priest, wrote on horrendous evils that go beyond what ordinary arguments can address. Eleonore Stump has argued that the biblical story of Job is a response to suffering of a specific kind. Any serious treatment keeps these personal voices in view.

Step-by-step explanation

Step 1: The argument stated

The argument can be put in a few steps. If God is all-powerful, God can prevent any evil. If God is all-knowing, God knows of every evil. If God is perfectly good, God would want to prevent evil. Yet evil exists. So, it seems, such a God does not exist.

Defenders note that each premise needs careful statement. All-powerful does not mean able to do what is logically impossible. Perfectly good does not mean that God must prevent every evil, if there are goods that cannot be had without allowing some. And evil is real, and no one should deny that. The debate turns on whether a good God could have a morally sufficient reason to permit the evils that are found in the world.

Step 2: The logical problem and the free will defense

Mackie’s version said that an all-powerful and all-good God would eliminate evil, so that the three statements are contradictory. Plantinga replied that a contradiction must be shown, not just suggested. He argued that it is possible that God could not create a world with moral good but no moral evil, because moral good requires free creatures, and free creatures can do wrong. If it is possible that every free creature God could create would go wrong at least once, then God and evil are not contradictory. This is the free will defense.

The defense does not claim to be true or to explain the actual reasons. It claims only that the contradiction is not proved. It works against the logical form and does not by itself answer the evidential form, nor does it explain natural evil. Plantinga proposed that natural evil might be caused by fallen angels or other free creatures, which many have found speculative. Most philosophers now accept that the logical problem as Mackie stated it has failed, though some remain unsatisfied with the details.

Step 3: The evidential problem

Rowe’s argument concerns the quantity and kind of evil. He asked about a fawn trapped in a forest fire that suffers for days and dies, with no one to know and no apparent good coming of it. He argued that it is likely there are evils like this for which God would have no sufficient reason to permit, and so it is likely that no God exists. A second form of the argument cites the large numbers of animals and humans that suffer, and the hiddenness of any good.

Responses fall into three kinds. Some argue that humans are poor judges of what reasons God might have, since human knowledge is limited. This is called skeptical theism, and it is pressed by Stephen Wykstra and others. Critics say this proves too much, since it makes moral judgment about God impossible. Others offer theodicies, accounts of the good that evil may serve, such as the building of character or the free will of creatures. And others hold that the existence of God is supported by other arguments, so that even if evil counts against it, the balance of evidence still favors God. Skeptics reply that the arguments for God are not strong enough.

Step 4: Kinds of evil and the personal side

The kinds of evil matter. Moral evil is attributed to human choice, which makes the free will defense relevant. Natural evil is harder, since no free human choice causes an earthquake. Animal suffering over millions of years before humans is a special case. Horrendous evils, which Adams describes, pose the problem that no later good seems to outweigh them for the person who suffered them.

The Christian tradition has always held that the problem of evil is not only a puzzle for argument. Job’s friends try to explain his suffering, and God rebukes them. The cross is, for Christians, the center of the answer, since God enters suffering in the person of the Son. Many writers, including Stump and Adams, argue that a response to the problem must address both the intellectual question and the lived pain. The next two lessons set out the main Christian responses and their limits.

  1. Where in my experience has the problem of evil been most pressing?
  2. What is the difference between the question Why does evil exist? and the question Why did this happen to me?
  3. Do I find the distinction between moral and natural evil helpful?
  4. How strong is the claim that we cannot know God’s reasons?
  5. Why might the Bible present the problem as a cry and not an argument?
  6. Which is harder for me, the intellectual or the personal form of the problem?

Examples

Mackie’s three statements

Mackie claimed that three statements cannot all be true: God is all-powerful, God is wholly good, and evil exists. He noted that if one is dropped, the problem goes away. Plantinga replied that to show a contradiction one needs another premise, such as that a good God would always eliminate evil, which is not obvious.

Rowe’s fawn

A lightning strike starts a forest fire, and a fawn is burned and suffers for days before dying. No human knows. Rowe asks whether it is likely that an all-good God had no way to prevent this without losing a greater good. Skeptical theists say that humans cannot know. Others offer theodicies. Skeptics say the case counts against God.

Ivan Karamazov

In Dostoevsky’s novel, Ivan describes children who are tortured and says that even if a final harmony were gained, he would return his ticket. The scene is not meant as a formal argument, but it has shaped how many people feel the problem. In the book, Alyosha gives no argument in reply, but a gesture of love.

Different perspectives

Catholic

Catholic teaching holds that God is good, that he permits evil only to bring a greater good, and that evil is a privation of good. The Catechism says in paragraph 309 that there is no quick answer to the question and that the whole of the Christian faith is the response. Catholic philosophers have contributed to both theodicy and defense.

Orthodox

Orthodox thought stresses that God is not the author of evil, and that death and suffering entered the world through sin and the fall. It stresses the victory of Christ over death in the resurrection, and tends to be wary of rationalist theodicies. Dostoevsky, an Orthodox writer, explored the question in the Brothers Karamazov.

Protestant

Protestants offer a range. Reformed writers stress God’s sovereignty and hidden purposes, with the cross as the center. Arminians and others emphasize free will. Plantinga, a Reformed philosopher, developed the free will defense. Others, like C. S. Lewis in The Problem of Pain, have written about suffering and moral growth.

Secular and atheist views

Many philosophers, such as Mackie, Rowe and Paul Draper, argue that evil counts strongly against theism. Some, like Hume, also doubt that the order of nature supports belief in a good God. Atheist philosophers differ on whether the logical argument is dead and whether the evidential argument is strong.

Jewish and other traditions

Jewish thinkers have a long tradition of protest and trust. The book of Job, the Psalms of lament and later reflection after the Holocaust, as in Elie Wiesel and Emil Fackenheim, show a faith that questions God. Buddhism and Hinduism have different accounts of suffering, in which there is no creator God to be justified.

Why it matters

The problem of evil is where belief in God is most tested, in life and in argument. A student who has looked at it honestly can speak to a person in pain without cliches, and can see the real strengths and limits of the arguments on both sides. It also helps to see that the Bible does not avoid the problem, but gives it a voice.

Common misunderstandings

Misunderstanding: The free will defense says that evil is good because it comes from freedom.

Correction: It does not. It says that the possibility of moral evil may be a cost of creating free creatures, and that this makes the logical contradiction unproven. It does not claim that evil is good.

Misunderstanding: Philosophers have settled that God does not exist because of evil.

Correction: No settlement exists. Most philosophers think the logical argument fails, and the evidential argument is still debated, with serious figures on both sides.

Misunderstanding: Christians pretend evil is not real.

Correction: The Christian tradition treats evil as real and serious, and some strands, such as the Psalms of lament and Job, press the complaint. Calling evil a privation does not mean it is unreal.

Misunderstanding: A theodicy is meant to console the sufferer.

Correction: A theodicy is an intellectual argument. Consolation is another task, and good pastoral care does not offer arguments to a person in grief. Job’s friends are rebuked for trying to explain.

Knowledge check

What is the difference between the logical and evidential problems of evil?

The logical problem claims that God and evil cannot both exist because they contradict. The evidential problem claims that evil does not contradict God but makes God’s existence unlikely, because of the amount or kind of evil. Most philosophers think the logical form has been answered, while the evidential form remains debated.

What is the free will defense?

It is Plantinga’s argument that it is possible that God could not create a world with moral good and no moral evil, because moral good requires free creatures, who may do wrong. This shows that God and evil are not logically contradictory. It does not claim to give God’s actual reasons.

State Rowe’s argument in brief.

Rowe argued that there appear to be evils, such as a fawn suffering in a forest fire, for which no greater good seems to justify their permission. He concluded that it is likely there are gratuitous evils, and so it is likely that no all-good God exists. Responses include skeptical theism and theodicies.

Distinguish moral, natural and horrendous evil.

Moral evil comes from human choices. Natural evil comes from nature, such as disease or earthquakes. Horrendous evil, a term from Marilyn Adams, is evil so deep that it threatens the value of a person’s life as a whole. Each kind raises different problems for responses to evil.

Think it through

  1. What do you think a good response to suffering should do beyond giving an argument?
  2. Does the distinction between a defense and a theodicy matter to you?
  3. How would you respond to a friend who says that evil proves there is no God, without pretending to know more than you do?

Independent assignment

The argument in your own words

In your own notebook, write about 450 words. State the problem of evil in your own words in four or five steps. Then mark the premise that you think is weakest and the one that is strongest, and explain why. Then write a paragraph on whether the logical or evidential form is more serious in your view. Do not send this to anyone.

Further study