Alvin Plantinga's free-will defense
Alvin Plantinga's free-will defense is a logical argument developed by the American analytic philosopher Alvin Plantinga and published in its final version in his 1977 book God, Freedom, and Evil.[1] Plantinga's argument is a defense against the logical problem of evil as formulated by the philosopher J. L. Mackie beginning in 1955.[2][3] Mackie's formulation of the logical problem of evil argued that three attributes ascribed to God (omniscience, omnipotence, and omnibenevolence) are logically incompatible with the existence of evil.
Plantinga's free-will defense[edit]
Plantinga's free-will defense begins by noting a distinction between moral evil and physical evil (Plantinga's defense primarily references moral evil), then asserting that Mackie's argument failed to establish an explicit logical contradiction between God and the existence of moral evil. In other words Plantinga shows that (1–4) are not on their own contradictory, and that any contradiction must originate from a theologian's implicit unstated assumptions, assumptions representing premises not stated in the argument itself. With an explicit contradiction ruled out, a theologian must add premises to the argument for it to succeed.[5] Nonetheless, if Plantinga had offered no further argument, then a theologian's intuitive impressions that a contradiction must exist would have remained unanswered. Plantinga sought to resolve this by offering two further points.[6]
First, Plantinga pointed out that omnipotence is the power to do all things logically possible, and thus God could not be expected to do things that are logically impossible according to modal logic.[7] God could not, for example, create square circles, act contrary to his nature, or, more relevantly, create beings with free will that would never choose evil.[8] Taking this latter point further, Plantinga argued that the moral value of human free will is a credible offsetting justification that God could have as a morally justified reason for permitting the existence of evil.[9] Plantinga did not claim to have shown that the conclusion of the logical problem is wrong, nor did he assert that God's reason for allowing evil is, in fact, to preserve free will. Instead, his argument sought only to show that the logical problem of evil was invalid.[10]
Plantinga's defense has received strong support among academic philosophers, with many agreeing that it defeated the logical problem of evil.[11][12][13][14] Contemporary atheologians[15] have presented arguments claiming to have found the additional premises needed to create an explicitly contradictory theistic set by adding to the propositions 1–4.
In addition to Plantinga's free-will defense, there are other arguments purporting to undermine or disprove the logical argument from evil.[13] Plantinga's free-will defense is the best known of these responses at least in part because of his thoroughness in describing and addressing the relevant questions and issues in God, Freedom, and Evil.
Additional objections and responses[edit]
Natural evil[edit]
A challenge to the free will defence is natural evil, evil which is the result of natural causes (e.g. a child suffering from a disease, mass casualties from a volcano).[28] Criticism of natural evil posits that even if for some reason an all-powerful and all-benevolent God tolerated evil human actions in order to allow free will, such a God would not be expected to also tolerate natural evils because they have no apparent connection to free will.[29][30] Patricia A. Williams says differentiating between moral and natural evil is common but, in her view, unjustified. "Because human beings and their choices are part of nature, all evils are natural".[31]
Advocates of the free will response propose various explanations of natural evils. Alvin Plantinga[32] references Augustine of Hippo,[33] writing of the possibility that natural evils could be caused by supernatural beings such as Satan.[34] Plantinga emphasizes that it is not necessary that this be true, it is only necessary that this possibility be compatible with the argument from freewill.[33] There are those who respond that Plantinga's freewill response might address moral evil but not natural evil.[35] Some scholars, such as David Griffin, state that free will, or the assumption of greater good through free will, does not apply to animals.[36][37] In contrast, a few scholars, while accepting that "free will" applies in a human context, have posited an alternative "free creatures" defense, stating that animals too benefit from their physical freedom though that comes with the cost of dangers they continuously face.[38]
The "free creatures" defense has also been criticized, in the case of caged, domesticated and farmed animals who are not free and many of whom have historically experienced evil and suffering from abuse by their owners. Further, even animals and living creatures in the wild face horrendous evils and suffering – such as burns and slow death after natural fires or other natural disasters or from predatory injuries – and it is unclear, state Bishop and Perszyk, why an all-loving God would create such free creatures prone to intense suffering.[38]