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. (shrink)

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. (shrink)

Alvin Plantinga’s evolutionary argument against naturalism argues that the probability of our possessing reliable cognitive faculties, given the truth of evolution and naturalism, is low, and that this provides a defeater for naturalism, if the naturalist in question holds to the general truths of evolutionary biology. Stephen Law has recently objected to Plantinga’s evolutionary argument against naturalism by suggesting that there exist conceptual constraints governing the content a belief can have given its relationships to other things, including behaviour . I (...) show that Law’s objection fails, since it offers an auxiliary hypothesis to naturalism which is itself improbable. I consider multiple variants of the CC thesis, demonstrating that each is improbable, and that any weaker version with greater prior probability is compromised by a failure to render the relevant datum – the reliability of our cognitive faculties – probable. Thus, Law’s objection to Plantinga’s argument fails. (shrink)

Alvin Plantinga’s Evolutionary Argument Against Naturalism aims to show that the conjunction of contemporary evolutionary theory (E) with the claim that there is no God (N) cannot be rationally accepted. Where R is the claim that our cognitive faculties are reliable, the argument is: The probability of R given N and E is low or inscrutable.Anyone who sees (1) and accepts (N&E) has a defeater for R, and this defeater cannot be defeated or deflected.Anyone who has an undefeated, undeflected defeater (...) for R has an undefeated, undeflected defeater for everything she believes.Therefore she has an undefeated, undeflected defeater for (N&E).Plantinga (2011) defends the second premise. It examines and rejects several candidate defeater defeaters and defeater deflectors. One candidate is Millikan’s teleosemantics. I show that Plantinga’s motives for rejecting teleosemantics as a defeater deflector are inadequate. I then show that teleosemantics is not on its own an adequate defeater deflector. Then I offer an additional premise that constitutes a defeater deflector in conjunction with teleosemantics. (shrink)

Plantinga's Evolutionary Argument Against Naturalism aims to show that naturalism is, as he puts it, ‘incoherent or self defeating’. Plantinga supposes that, in the absence of any God-like being to guide the process, natural selection is unlikely to favour true belief. Plantinga overlooks the fact that adherents of naturalism may plausibly hold that there exist certain conceptual links between belief content and behaviour. Given such links, natural selection will favour true belief. A further rather surprising consequence of the existence of (...) such links is this: even if semantic properties are epiphenomenal, unguided evolution will still favour true belief. (shrink)

Recent authors have drawn attention to a new kind of defeating evidence commonly referred to as higher-order evidence. Such evidence works by inducing doubts that one’s doxastic state is the result of a flawed process – for instance, a process brought about by a reason-distorting drug. I argue that accommodating defeat by higher-order evidence requires a two-tiered theory of justification, and that the phenomenon gives rise to a puzzle. The puzzle is that at least in some situations involving higher-order defeaters (...) the correct epistemic rules issue conflicting recommendations. For instance, a subject ought to believe p, but she ought also to suspend judgment in p. I discuss three responses. The first resists the puzzle by arguing that there is only one correct epistemic rule, an Über-rule. The second accepts that there are genuine epistemic dilemmas. The third appeals to a hierarchy or ordering of correct epistemic rules. I spell out problems for all of these responses. I conclude that the right lesson to draw from the puzzle is that a state can be epistemically rational or justified even if one has what looks to be strong evidence to think that it is not. As such, the considerations put forth constitute a non question-begging argument for a kind of externalism. (shrink)

This paper engages with two compelling challenges to physicalism, each designed to show that the nature of experience is elusive from the standpoint of physical science. It is argued that the physicalist is ultimately well placed to meet both challenges.

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. (shrink)

What are the philosophical views of contemporary professional philosophers? We surveyed many professional philosophers in order to help determine their views on 30 central philosophical issues. This article documents the results. It also reveals correlations among philosophical views and between these views and factors such as age, gender, and nationality. A factor analysis suggests that an individual's views on these issues factor into a few underlying components that predict much of the variation in those views. The results of a metasurvey (...) also suggest that many of the results of the survey are surprising: philosophers as a whole have quite inaccurate beliefs about the distribution of philosophical views in the profession. (shrink)

An irrealist conception of a given region of discourse is the view that no real properties answer to the central predicates of the region in question. Any such conception emerges, invariably, as the result of the interaction of two forces. An account of the meaning of the central predicates, along with a conception of the sorts of property the world may contain, conspire to show that, if the predicates of the region are taken to express properties, their extensions would have (...) to be deemed uniformly empty. The question then becomes whether the predicates are best understood as expressing properties, and hence as founded on error, or whether they ought to be understood along non-factualist lines.z Historically, irrealist models were developed primarily in connection with evaluative discourse, although as physicalism has flourished and as reductionist programs have failed, their application has been extended to many other domains. Indeed, it is one of the more influential suggestions in contemporary philosophy of mind that they apply even to ordinary belief/desire psychology. A correct understanding of the semantics and metaphysics of content-based psychology leaves us, so the proponents of the in-. (shrink)

Many epistemologists are enamored with a defeat condition on knowledge. In this paper we present some implementation problems for defeatism, understood along either internalist or externalist lines. We then propose that one who accepts a knowledge norm of belief, according to which one ought to believe only what one knows, can explain away much of the motivation for defeatism. This is an important result, because on the one hand it respects the plausibility of the intuitions about defeat shared by many (...) in epistemology; but on the other hand, it obviates the need to provide a unified account of defeat which plays well with the most plausible views of how knowledge fits with evidential probability. (shrink)

This paper will examine two strategies by which religious believers might attempt to defend the rationality of religious belief. The first strategy is a “fine tuning argument.” The main shortcoming of that strategy is that it ignores the crucial issue of the appropriate prior probabilities. The second strategy is what might be called a “trust” strategy. According to this strategy, a belief that is based on trusting someone who knows something is thereby also an instance of knowledge. This strategy might (...) suffice in some respects, but it involves reliance on a mechanism that is doubtful as a prototype for all of our beliefs. (shrink)

The following is not a successful skeptical scenario: you think you know you have hands, but maybe you don't! Why is that a failure, when it's far more likely than, say, the evil genius hypothesis? That's the question.<br><br>This is an earlier draft.

There are two different kinds of theories of the concept of epistemic defeat. One theory begins with propositional relationships, only by implication describing what happens in the context of a noetic system. Such a theory places inforrmation about defeat up front, not informing us of how the defeat relationships play out in the context of actual belief, at least not initially. The other theory takes a back door to the concept of defeat, assuming a context of actual belief and an (...) entire noetic system, and describing defeat in terms of what sort of doxastic and noetic responses would be appropriate to the addition of particular pieces of information. Where the house is the noetic structure itself, the front door approach characterizes the concept of defeat in terms of the propositional contents a belief might have, thus characterizing defeat at the front door. The backdoor approach characterizes defeat in terms of what leaves the house, in terms of beliefs that exit the noetic system in response to changes to it, in terms of what the staff of a well-run household kicks out the backdoor for making a mess of things. Alvin Plantinga’s theory of epistemic defeat is a back-door theory, and here I will argue that his theory and approaches like it will be unable to explicate accurately the concept of epistemic defeat. I will argue that a front door approach is needed rather than a back door approach. (shrink)