Introduction: The Logical Argument From Evil
“Is [God] willing to prevent evil, but not able? then is he impotent. Is he able, but not willing? then is he malevolent. Is he both able and willing? Whence then is evil?”
Hume, David. Dialogues Concerning Natural Religion, in: Dialogues Concerning Natural Religion and Other Writings. Coleman Dorothy (ed.), Cambridge University Press
The list of arguments for and against the existence of gods/God is very long, so it is useful to bring some order into the debate by distinguishing two different types of arguments. There are purely a priori arguments which try to establish God’s (non-)existence without invoking any knowledge from experience, such as the ontological argument or the incompatible-properties argument. The other class of arguments start from empirical observations and moves via either deductive or inductive reasoning to conclusions about God’s existence. Examples are the fine-tuning argument and the argument from evil.
The argument from evil is perhaps the strongest and most compelling argument against God’s existence. It is part of the debate on the problem of evil, the attempt of reconciling God’s existence with that of tremendous suffering and evil. The argument from evil is intended to show that this can’t be done and that, since we observe tremendous suffering and evil, God does not exist. What is so intriguing about the argument from evil is that it offers a way of arguing against God’s existence that is not in principle different from how we falsify scientific theories in the hypothetico-deductive model or how we disconfirm them in the Bayesian model.
There are two basic approaches to the argument, one deductive/logical and the other inductive/probabilistic/evidential. The logical argument from evil occupied the centre stage of the debate for most of history, whereas nowadays the evidential argument gets most of the attention. In this article we look at the logical argument, in the follow up article at the evidential argument.
The Empirical Premise: Widespread Horrendous Suffering
Both, the logical and the evidential argument from evil invoke an empirical premise on the existence and scope of evil in the world. One of the clearest instances of evil is suffering, and most versions of the argument contain a premise involving suffering. To get a feeling for the different types, the pervasiveness, and the horrendousness of suffering on Earth, we can consider the following short catalogue of suffering:
Human Suffering Induced by Humans: Sophisticated torture has existed at least since antiquity and has been used for a variety of purposes, among them sadistic pleasure. Some of the torturing techniques are so horrible it is difficult to believe humans have used them on other humans. In his book Discipline and Punish, Michel Foucault offers a vivid and detailed description of the torture and execution of Robert-Francois Damiens for the attempted assassination of King Louis XV. Torture is sometimes part of genocide, the systematic destruction of all or part of a racial, ethnic, religious or national group. The last century has seen the Holocaust and many other genocides.
Animal Suffering Induced by Humans: Non-human animals are used by humans for a variety of purposes, among them in vivo testing of medication, production of fur and leather for clothes, and food. In the process humans cause a massive amount of suffering for these animals. A particularly salient case of such suffering is the failure of stunning methods before slaughter, where animals are either stunned again or slaughtered while partly or fully conscious. The Scientific Veterinary Committee of the European Commission came to the conclusion that “in 5 to 10% of cattle captive bolt stunning is not applied correctly. Inadequate facilities for the presentation of heads of animals to the operators is thought to be the major cause of this problem. Animals may remain conscious or regain consciousness very soon either due to inappropriate shooting position or cartridge.” (Day and Whittington 1990)
Natural Human Suffering: There are numerous physical and mental diseases causing vast amounts of suffering and death, many of which are known and need not be mentioned here. Here is a case of a little known but especially nightmarish disease: Fibrodysplasia Ossificans Progressiva is a rare genetic condition which causes the body’s repair mechanism to turn fibrous tissue (including muscle, tendon, and ligament) into bone material spontaneously or when damaged. Sufferers are slowly imprisoned by their own skeletons and suffer from a variety of symptoms, among them a complete loss of mobility of the affected joints and tissue, including inability to fully open the mouth, limiting speech and eating. We have no cure for this disease. Other natural occurrences of human suffering are due to earthquakes, tsunamis, and other natural disasters, or simply old age and its biological consequences.
Natural Animal Suffering: One of the largest pools of suffering on Earth is one that we’re often not aware of, namely that of wild-animal suffering. The life of an animal in the wild is a struggle for survival and resources and often involves moments of fear or even physical pain, and frequently a gruesome death from either injury, diseases, or hunger. Particularly horrifying examples of such deaths are provided by the Ichneumonidae larvae, the emerald cockroach wasp larvae, and the Mermithid Worm which slowly eat their hosts alive. Moreover, all of this is an essential part of the mechanism that brought about the variety of species we observe today: one element of natural selection is differential survival, which means that only the well adapted animals are successful in the struggle for survival. This means that wild-animal suffering has been present since the beginning of conscious life on Earth. Wild-animals massively outnumber factory-farmed animals and domesticated animals, which gives us reason to think that the amount of wild-animal suffering massively exceeds that of factory-farmed animals, even if the life of a factory-farmed animal would turn out to be worse on average than that of a wild animal.
This short catalogue of examples of suffering from the four different categories should be sufficient to motivate what we can call the Widespread Horrendous Suffering Thesis (WHST), the claim that the amount of horrendous suffering on Earth is vast and beyond human imagination. WHST is an empirical claim and as such could have turned out to be false. But it just so happens that we live in a universe in which WHST holds, and this is the basis for the argument from evil.
The Logical Argument
Adherents of the logical argument from evil think that the existence of evil conclusively disproves God’s existence. John Leslie Mackie for example, the philosopher who coined the term “logical problem of evil”, thought that not only can it be shown that religious beliefs “are positively irrational, that the several parts of the essential theological doctrine are inconsistent with one another, so that the theologian […] must be prepared to believe, not merely what cannot be proved, but what can be disproved from other beliefs that he also holds.” (Mackie 1955).
The philosopher Michael Tooley (2008, p. 99 f.) offers the following version of the logical argument from evil, which, if sound, would disprove God’s existence:
1) Any omniscient being knows about every possible way in which any evil can come into existence.
2) Any omnipotent being who knows of every possible way in which any evil can come into existence has the power to prevent all evils.
3) Any morally perfect being wants to prevent all evil.
4) Any omniscient, omnipotent, and morally perfect being both has the power to prevent all evils, and wants to prevent all evils.
5) If there is a being who both has the power to prevent all evils, and wants to prevent all evils, then no evils exist.
6) If there is an omniscient, omnipotent, and morally perfect being, no evils exist.
7) Evils exist.
8) There is no omniscient, omnipotent, and morally perfect being.
9) If God exists, he is omnipotent, omniscient, and morally perfect.
10) God does not exist.
The argument is clearly valid, which means that necessary, if the premises are correct the conclusion is true as well. Premise 7 follows from WHST and is the empirical premise of the argument. Sentence 6 is making an empirical prediction based on theism, very much the same way we can make empirical predictions based on Newtonian mechanics. The argument looks like an application of the hypothetico-deductive model of scientific reasoning: we start with a hypothesis, deduce empirical predictions from the hypothesis, and then discard the hypothesis because the predictions turn out to be wrong.
Are all the premises of the argument true? Due to arguments by various philosophers, among them notably Alvin Plantinga (1974), only few philosophers now believe that the argument is sound. The reason is that it’s far from clear that a morally perfect being would want to prevent all evils. What if there are some great goods which can only be achieved by allowing some evils? A morally perfect being might then want to allow these evils in order to create these goods. This might or might not be plausible, but it is an idea accepted by many theists. And this is already enough to sabotage Mackie’s ambitious project of demonstrating that they hold logically inconsistent beliefs.
But this does not mean that there is no good version of the argument from evil. Deductive arguments are extremely strong, but they do not succeed very often. Most good arguments we’re familiar with are inductive arguments, and there is an inductive version of the argument from evil: the evidential argument.
Daly, C. C., & Whittington, P. E. (1990). A survey of commercial practices used in the stunning of cattle. Unpublished but reported in The Times of, 23.
Mackie, J. L. (1955). Evil and omnipotence. Mind, 200-212.
Plantinga, A. (1974). God, freedom, and evil. Wm. B. Eerdmans Publishing.
Tooley, M. (2008). The Argument from Evil and the Existence of God. Knowledge of God.