Online research in philosophy

In this, the first book to address the ongoing debate, Plantinga presents his influential thesis and responds to critiques by distinguished philosophers from a ...

In "Warrant and Proper Function" Plantinga argues that atheistic Naturalism is self-defeating. What is the probability that our cognitive faculties are reliable, given this Naturalism and an evolutionary explanation of their origins? Plantinga argues that if the Naturalist is modest enough to believe that it is irrational to have any belief as to the value of this probability, then he is irrational even to believe his own Naturalism. I suggest that Plantinga's argument has a false premise, and that even if his argument were sound there would be reasons for doubting whether the Naturalist should respond to it by abandoning his Naturalism.

Alvin Plantinga has famously argued that metaphysical naturalism is self-defeating, and cannot be rationally accepted. I distinguish between two different ways of understanding this argument, which I call the "probabilistic inference conception", and the "process characteristic conception". I argue that the former is what critics of the argument usually presuppose, whereas most critical responses fail when one assumes the latter conception. To illustrate this, I examine three standard objections to Plantinga's evolutionary argument against naturalism: the Perspiration Objection, the Tu Quoque Objection, and the "Why Can't the Naturalist Just Add a Little Something?" Objection. I show that Plantinga's own responses to these objections fail, and propose counterexamples to his first two principles of defeat. I then go on to construct more adequate responses to these objections, using the distinctions I develop in the first part of the paper.

Alvin Plantinga has argued that evolutionary naturalism (the idea that God does not tinker with evolution) undermines its own rationality. Natural selection is concerned with survival and reproduction, and false beliefs conjoined with complementary motivational drives could serve the same aims as true beliefs. Thus, argues Plantinga, if we believe we evolved naturally, we should not think our beliefs are, on average, likely to be true, including our beliefs in evolution and naturalism. I argue herein that our cognitive faculties are less reliable than we often take them to be, that it is theism which has difficulty explaining the nature of our cognition, that much of our knowledge is not passed through biological evolution but learned and transferred through culture, and that the unreliability of our cognition helps explain the usefulness of science.

In his recently published two-volume work in epistemology,1 Alvin Plantinga rounds out the discussion (in characteristic fashion) with a subtle and ingenious argument for a striking claim: in this case, his conclusion is that belief in evolutionary naturalism is irrational. Now this claim is not of itself so very surprising; the tantalizing feature here lies rather in the nature of the argument itself. Plantinga contends that taking seriously the hypothesis of evolutionary naturalism [hereafter, N&E] ought to undermine one's confidence in the reliability of our basic cognitive faculties. And if one withholds belief in cognitive reliability, it seems that one ought to likewise refrain from believing propositions that are the output of such faculties. And, for evolutionary naturalists, one such output is belief in evolutionary naturalism itself. Hence, quite apart from comparative evidential considerations that might lead one to prefer theism (or one of its competitors) to N&E, but rather owing to a sort of internal inconsistency (in a suitably broad sense), belief in N&E is shown to be epistemically defective. A bold and intriguing suggestion indeed. Let us take a closer look.

In Chapter 12 of Warrant and Proper Function, Alvin Plantinga constructs two arguments against evolutionary naturalism, which he construes as a conjunction E&N .The hypothesis E says that “human cognitive faculties arose by way of the mechanisms to which contemporary evolutionary thought directs our attention (p.220).”1 With respect to proposition N , Plantinga (p. 270) says “it isn’t easy to say precisely what naturalism is,” but then adds that “crucial to metaphysical naturalism, of course, is the view that there is no such person as the God of traditional theism.” Plantinga tries to cast doubt on the conjunction E&N in two ways.His “preliminary argument” aims to show that the conjunction is probably false, given the fact (R) that our psychological mechanisms for forming beliefs about the world are generally reliable.His “main argument” aims to show that the conjunction E&N is self-defeating — if you believe E&N , then you should stop believing that conjunction.Plantinga further develops the main argument in his unpublished paper “Naturalism Defeated” (Plantinga 1994).We will try to show that both arguments contain serious errors.

In the final chapter of Warrant and Proper Function, Alvin Planting a presents an “evolutionary argument against naturalism” (where naturalism is the claim that there are no supernatural beings). According to this argument, the conjunction of naturalism and evolution cannot be rationally believed by anyone who understands its epistemic implications. In this paper, I argue that if Plantinga’s evolutionary argument is sound, it follows that (what I call) perceptive naturalists have no propositional knowledge. Since it is plausible that perceptive naturalists do have some propositional knowledge, I infer that the evolutionary argument (EA) is unsound. However, I conclude the paper with the suggestion that even if EA is unsound, it may still provide important insights about the epistemic shortcomings of naturalism.

Only in rational creatures is there found a likeness of God which counts as an image . . . . As far as a likeness of the divine nature is concerned, rational creatures seem somehow to attain a representation of [that] type in virtue of imitating God not only in this, that he is and lives, but especially in this, that he understands (ST Ia Q.93 a.6).