In the last post I gave a brief introduction to the study of the problem of evil, covering the two basic forms of the problem and some preliminary definitions. You can view that post here. This week I want to dig a little deeper into the logical problem of evil and see if it can be answered.
THE LOGICAL PROBLEM
The logical problem of evil says that God (as defined by Scripture), and evil cannot both logically exist in the same possible world. Since evil and suffering clearly exist, God must not exist. Two mutually exclusive things cannot coexist. For example, a poison that would kill any creature is a perfectly logical possibility, yet so is the idea of a creature that could drink any poison and live. However, it is logically impossible for both to exist in the same possible world. This is the type of contradiction alleged by the logical problem. Even assuming that God could exist, and that evil could exist, both could not exist in the same possible world. Since it is evident that evil exists in our world, God cannot exist.
Instead of examining David Hume’s version of the problem as mentioned in the last post, we will turn to someone a little more recent: the Australian philosopher John Mackie. Mackie writes, “In its simplest form the problem is this: God is omnipotent; God is wholly good; yet evil exists. There seems to be some contradiction between these three propositions, so that if any two of them were true the third would be false.” Out of all the responses to the logical problem of Evil, Alvin Plantinga’s recent response is without question the most well known. In God, Freedom, and Evil, Plantinga attempts to show that there is no logical problem with the three propositions (1) God is omnipotent, (2) God is wholly good, and (3) Evil exists, as Mackie posits. In apparent contradictions such as these, all that needs to be produced is an additional proposition that is consistent with each of the propositions already mentioned. Consider this set for an example: (A) Tom despises garbage dumps, (B) It is within Tom’s power to avoid all garbage dumps, and (C) Tom spends hours every day at a garbage dump. Mackie’s words fit here as well “There seems to be some contradiction between these three propositions,” however a fourth proposition can make sense of it all. (D) Tom makes 50 dollars an hour working at the city garbage dump. Likewise, all Plantinga has to do is find an additional proposition that is consistent with each in the set 1-3.
Finding a proposition that would be consistent with both Christian theism, and propositions 1-3 above is actually quite simple. Plantinga gives us this proposition: (3’) “God creates a world containing evil and has a good reason for doing so.” It may sound simplistic, but it is immediately apparent that the “problem,” as stated, is less than an explicitly logical one. However, it would be less than honest to stop here and say that (3’) has solved Mackie’s problem. This is because Mackie himself realized that 1-3 where not explicitly contradictory. He proceeded to propose three more propositions which he believed would seal the deal.
(4) “Good is opposed to evil, in such a way that a good thing always eliminates evil as far as it can” and, (5) “there are no limits to what an omnipotent thing can do.” From these clarifications of what Mackie means by “good” and “omnipotent” a further proposition could be deduced which would finally produce a logical problem. He writes, (6) “a good, omnipotent being eliminates evil completely,” and of course this would be a direct contradiction to 1-3 (if we include the fact of God’s omniscience—an easy escape-route for the theist that Mackie seemed to have overlooked. For example, if God was oblivious to evil He could not be morally responsible to do anything about it). We will add God’s omniscience to proposition (1). So far the propositions are as follows:
- God is omnipotent and omniscient.
- God is wholly good.
- Evil exists.
- A good thing always eliminates evil as far as it can.
- There are no limits to what an omnipotent thing can do.
- A good omnipotent being eliminates evil completely.
It is true that (6) logically follows from (4) and (5), and that if (6) is true then 1-3 cannot be, and therefore God cannot exist if Evil does. But are 4-5 true? Not obviously. If either is found lacking, then (6) breaks down, and the contradiction no longer exists. Plantinga first tackles proposition (5). “There are no limits to what an omnipotent thing can do.” This is clearly not true; no matter how powerful a being is, it cannot do what is logically impossible for example. God cannot create another uncreated being, or make a rock too heavy to lift, or both exist and not exist. So, immediately we must rephrase (5) to “There are no nonlogical limits to what an omnipotent thing can do,” and with it proposition (6). Proposition (6) now reads, “A good, omnipotent being eliminates all evil that is logically possible to eliminate.” Strictly speaking the contradiction is already eradicated (6 no longer explicitly contradicts 1-3), but there is still more.
Consider now, (4), “A good thing always eliminates evil as far as it can.” This is not strictly true either. Consider this example: in order to graduate on time, Kyle was forced to take an 8 A.M. class three days a week in the final semester of his senior year (a period which he consistently tried to avoid). Doing so required Kyle to wake up earlier than he preferred, to miss seeing his wife in the mornings, and to experience much heavier traffic than he had in previous semesters. Upon hearing of Kyle’s dilemma, his professor contrived a solution. The next day Kyle received an email explaining that he had been graciously expelled him from his 8A.M. class. From that time on, Kyle could sleep in every morning, could eat breakfast with his wife, and would miss the brunt of the morning traffic. His professor had eliminated the evil conditions that Kyle was facing. While few would say that the professor’s actions where “good”—Kyle could no longer graduate on time—no one can deny that they where consistent with (4). Therefore proposition (4) should be modified to read, “A good thing always eliminates evil as far as it can, as long as doing so does not create a greater evil or obstruct a good that outweighs that evil.” Proposition (6) now needs to be updated to reflect the changes to (4): (6) “A good, omnipotent being eliminates all evil that is logically possible to eliminate and which does not create a greater evil or obstruct a good that outweighs that evil.”
In updating the entire set it becomes clear that the alleged contradiction has disappeared.
- God is omnipotent and omniscient
- God is wholly good
- Evil exists
- A good thing always eliminates evil as far as it can as long as doing so does not create a greater evil, or obstruct a good that outweighs that evil
- There are no nonlogical limits to what an omnipotent thing can do
- A good, omnipotent being eliminates all evil that is logically possible to eliminate and which does not create a greater evil or obstruct a good that outweighs that evil.
Clearly, (6) does not explicitly contradict 1-3, and in reality the theist’s work is done. All that really needed to be shown was that 1-3 (or the expanded 1-6) does not contain a contradiction. The atheist must now attempt to argue that there is no logically-possible scenario in which God could not eliminate evil without either creating a greater evil or obstructing a greater good. On the other hand, the theist, if he so desired, could postulate such a scenario and call the game. Doing so is beyond the scope of this post, besides, many have already done this work. One such example is Plantinga’s “Free-Will Defense” detailed in God, Freedom, and Evil (the book in which much of the preceding logic originated). Plantinga’s Free-Will Defense (FWD) is so well developed that it has almost entirely eradicated the logical problem of evil from the arguments of serious philosophers today. It must be understood that whether or not one believes in the truth of his scenario is irrelevant; in order for it to fail it must be shown to be logically impossible since the logical problem of evil charges the theist with a logical contradiction.
It is clear from Plantinga’s work on this subject that there is no logical inconsistency between the existence of God and our experience of evil. Next time on the blog we will consider a more prevalent version of the problem used today.
See Ronald Nash for an explanation of “Possible Worlds.” Ronald H. Nash, Life’s Ultimate Questions (Zondervan, 1999), 209–227.
Basil Mitchell, The Philosophy of Religion (Oxford University Press, USA, 1971), 92–93.
Plantinga, God, Freedom, and Evil, 26.
Mitchell, The Philosophy of Religion, 93.
McCune, A Systematic Theology of Biblical Christianity Vol. 1, 218–219; Plantinga, God, Freedom, and Evil, 17–18.
Plantinga, God, Freedom, and Evil, 21.
Mitchell, The Philosophy of Religion, 93.
Plantinga, God, Freedom, and Evil.
Chad Meister, Introducing Philosophy of Religion (Routledge, 2009), 134.
Douglas Groothuis, Christian Apologetics: A Comprehensive Case for Biblical Faith (IVP Academic, 2011), 631.