Alvin Plantinga

My interest in Warranted Christian Belief is in this question: Is it rational, or reasonable, or justified, or warranted to accept Christian belief? But there is a prior question: Is the very idea of Christian belief coherent? Many theologians and others believe that there is real difficulty with the idea that our concepts could apply to such a being as the Christian God, and that this constitutes a serious problem for Christian belief: Christian belief involves the belief that it is possible to think of, refer to, and predicate properties of God, but in fact none of these things are possible, because human concepts cannot apply to God. In this chapter and the next, I examine this objection to Christian belief, turning in this chapter to the thought of Immanuel Kant. Against the opinions of some, I argue that there is no good reason provided by Kant for the conclusion that our concepts do not apply to God.

In this chapter, a segment from my book Warrant and Proper Function, I argue that propositions cannot be concrete objects. In particular, I examine various ways in which the concretist might explain what it is for a proposition to be possible or necessary. I then demonstrate that the concretist is forced either to count far too many propositions as necessary or hold that blatant contradictions are possible. I conclude the chapter by suggesting that abstract objects, such as propositions, can stand in causal relations. Thus, the fact that propositions are not concrete does not entail the falsity of the causal requirement – i.e., the requirement that a knower stands in a causal relation to the object of knowledge.

In order to achieve a deeper understanding of warrant, I turn in this chapter to a closer look at the idea of a design plan. I do so under the following six section headings: the max plan versus the design plan, unintended by‐products, functional multiplicity, the distinction between purpose and design, trade‐offs and compromises, and defeaters and overriders. In connection to the notion of trade‐offs and compromises in our cognitive design plan, I take up the subject of Gettier problems, trying to understand what really underlies Gettier situations and then seeing how these situations look from the vantage point of my conception of warrant. While Gettier problems do not in fact plague my account of warrant, considering them nonetheless enables us to deepen our analysis of warrant. I close the chapter with a brief argument for the conclusion that my account of warrant qualifies as an example of naturalized epistemology.

In this chapter, I point out a few salient features of my account of warrant as it applies to perception and perceptual warrant. On my account, a perceptual judgment of mine constitutes knowledge if and only if that judgment is true, sufficiently strong, and produced by cognitive faculties that are successfully aimed at truth and functioning properly in an epistemic environment that is right for human perceptual powers. After a brief discussion of perceptual experience, I argue that ordinary perceptual beliefs are basic: they are not formed on the evidential basis of other beliefs I hold. While perceptual judgments are not formed on the basis of beliefs about my experience, they are, nonetheless, formed on the basis of experience, and so I take a quick look at that claim. In the final section of the chapter, I briefly take up questions about learning to perceive, and entertain the position that many perceptual judgments are only partially basic: not formed solely on the evidential basis of other beliefs, but formed partly on the basis of present perception and partly on the basis of beliefs about what things look like.

In this essay, I consider several objections raised by John Pollock against my account of modality. I define possibilism – i.e., the view that there is a property that does not entail existence, but is entailed by every property – and then give a more adequate definition of actualism based on its disagreement with possibilism. Pollock argues that the property of nonexistence is such that objects exemplify it in worlds in which they do not exist and based on this fact concludes that serious actualism is false. I give an argument that nonexistence is necessarily unexemplified and a separate argument for the conclusion that serious actualism is true. I conclude the essay by arguing that it does make a difference whether we accept existentialism or essentialism.

Existentialism is the claim that quidditative properties and singular propositions are ontologically dependent upon the individuals they involve. In this essay, I consider two arguments for existentialism and find them both unconvincing. I then give an argument against the existential thesis that singular propositions are ontologically dependent on contingent objects. I conclude the essay by defending my argument against potential existentialist objections. In the process, I defend the claim that serious actualism – i.e., the view that no object could have had a property without existing – is true.

In this chapter, I continue my explanation of how my account of warrant works in the main areas of our cognitive life, here examining how warrant works with respect to beliefs about other persons and beliefs furnished by testimony. As regards the first topic, I am concerned with the question of how our beliefs ascribing mental states to others acquire warrant. I examine three possible answers to this question, namely, that such beliefs acquire warrant by means of analogical arguments, that they do so by way of being scientific hypotheses, or that they do so by means of Wittgensteinian criteria. I argue that none of these answers is correct, and then suggest an answer that is both closer to the truth and more in line with the general theory of warrant I propose. Turning next to testimony, I explore some of its salient characteristics, argue that testimonial evidence is a basic sort of evidence for us and, finally, show how my account deals with Gettier problems involving testimony.

In this chapter, I continue to argue that naturalistic epistemology flourishes best in the garden of supernaturalistic metaphysics. I do so by presenting two epistemological arguments against metaphysical naturalism; the first argument is for the falsehood of naturalism, the second, and more developed, is for the conclusion that it is irrational to accept naturalism. Crucial to both arguments is the estimation of the value of a certain conditional probability, P), where R is the proposition that our cognitive faculties are reliable, N is metaphysical naturalism, E is the proposition that our cognitive faculties arose by way of the mechanisms of evolution, and C is a complex proposition stating what cognitive faculties we have and what sorts of beliefs they produce. In the second argument I contend that it is quite plausible to think either that the rational attitude to take towards the conditional probability mentioned above is the judgment that it is low or that the rational attitude is agnosticism with respect to it, and, in either case, the devotee of N & E has a defeater for any belief he holds, including N. Further, since this defeater is an ultimately undefeated defeater, it is irrational to accept N, since it is irrational to accept any proposition such that one knows one has an ultimately undefeated defeater for it.

The account of warrant I propose, utilizing the notion of proper function as it does, is an example of naturalistic epistemology: it invokes no kind of normativity not to be found in the natural sciences; in this chapter and the next, I argue that naturalism in epistemology can flourish only in the context of supernaturalism in metaphysics. To do so, I argue that there is no satisfactory naturalistic explanation or account of the notion of proper function. I consider proposals for such an account that can be drawn from the work of John Pollock, Ruth Millikan, and John Bigelow and Robert Pargetter, but find in each case that the proposed account is inadequate. I then consider the possibility that the notion of proper function should be thought of as useful fictions. After some critical comments about this possibility, I proceed to point out that if one is convinced that there really is such a thing as warrant and that there really is such a thing as proper function, and also thinks that there is no naturalistic analysis of these notions, then one has a powerful argument against naturalism.

In circumstances where one proposition A is propositional evidence for another proposition B, my believing A can confer warrant upon B. I use the term “epistemic probability” to refer to the relationship between a pair of propositions A and B when A is propositional evidence for B; more precisely, in those cases, I shall say that the epistemic conditional probability of B on A is high. In this chapter and the next, I concern myself with an analysis of epistemic conditional probability. The first thing to see, in trying to get a general grasp of this topic, is to note the divide between epistemic probability and objective probability. In this chapter, I distinguish the former from the latter and point out some debilitating problems with the three main accounts of the former ; in the next chapter, I propose what I hope is a better substitute.

In the first two chapters of Warrant and Proper Function, I presented my account of warrant; in the next seven chapters, I provide an explanation of how my account works in the main areas of our cognitive life. In this chapter, I begin this explanation by examining how warrant works with respect to self‐knowledge and memory. In the course of examining self‐knowledge and its relationship to warrant, I first argue against Derek Parfit's claim that we do not know and cannot justifiably believe that there is such a thing as a persisting subject of experience that is distinct from any of those experiences of which it is the subject. Second, I briefly argue that the beliefs that we are neither our brains nor our bodies are beliefs that have a good deal of warrant for us. Turning next to memory, I provide a brief discussion of the phenomenology of memory and argue that typical memory beliefs are basic and are capable of having a great deal of warrant for us.

Broadly taken, the term “induction” denotes our whole nondeductive procedure of acquiring, maintaining, and discarding beliefs about what is so far unobserved or undetected or unknown. In this chapter, I examine induction from the perspective of my account of warrant. I first take up what is now referred to as “the old riddle of induction,” rejecting David Hume's claim that inductive reasoning is not rationally justified and defending the view that beliefs formed on the basis of inductive reasoning can have warrant. I then turn to Nelson Goodman's ruminations on grue and the “new riddle of induction,” which is the question: what makes a property projectible? I reject Goodman's own solution to this problem, examine other inadequate solutions, and then suggest that an answer can be found by making reference to the proper function of the human intellect; projectible properties are just those properties that a properly functioning adult human being in our circumstances will in fact project.

In Ch. 8, I distinguished epistemic probability from objective probability and then pointed out some debilitating problems with the three main accounts of epistemic probability. In this chapter, I propose my own account of epistemic probability. I first distinguish between two sides to epistemic probability, which I call the objective component and the normative component. In typical cases where we assert that some proposition is epistemically probable, two things get asserted: that the proposition is objectively probable with respect to the evidence, and that it is rational to place a high degree of confidence in the proposition, given the circumstances of having as evidence what in fact we do have as evidence. Attempting to unpack these two components, I sketch the view that the normative component of the epistemic conditional probability of A on B is the interval containing the degrees of belief a rational person could have in A, provided she believed B and was aware that she believed B, considered the evidential bearing of B on A, had no other source of warrant for B or its denial, and had no defeater for the warrant, if any, accruing to A or its denial by virtue of being thus believed on the basis of B.

In this chapter, I examine the contrast between foundationalism and coherentism, and consider evidentialism, a special variety of foundationalism. After arguing that the central tenet of coherentism is that the sole source of warrant is coherence, I argue that coherentism is mistaken and endorse foundationalism. I then offer some brief comments on the inadequacy of classical foundationalism and contrast classical foundationalism to the sort of foundationalism I endorse, which I call Reidian foundationalism. I next turn to an examination of evidentialism, specifically the evidentialism of William Alston, Richard Feldman and Earl Conee. Taking “evidence” in a sufficiently broad sense, I concur with the AFC view in its claim that whenever some belief B has warrant for an agent S, it is the case that S has evidence for B; I also argue, however, that having evidence is not sufficient for warrant – proper function is also required.

In this essay, I raise three topics with regards to Roderick Chisholm's account of the idea of an individual essence. First, I give an argument for the claim that objects have more than one essence. Second, I defend the view that someone can know a proposition entailing someone else's essence. Third, I argue that existentialism is false. I demonstrate this by pointing out that existentialism's central claim – that the proposition E exists and the object x does not is impossible – is false; this proposition turns out to be possible after all on the existentialist account of possibility.

I begin the chapter by considering the distinction between modality de re and modality de dicto in the works of Aristotle, St. Thomas Aquinas, G. E. Moore, and Norman Malcolm. I then consider two similar objections to modality de re brought by William Kneale and W. V. Quine. Both of these objections fail because they depend on a de re/de dicto confusion. Moreover, I formulate a general rule for correlating propositions that express modality de re with propositions that express modality de dicto. The formulation I offer relies heavily on proper names and I conclude by suggesting further routes of inquiry into the connection between proper names and essentialism.

In this chapter, I examine a priori knowledge from the perspective of my account of warrant. According to the epistemological tradition, what is known a priori is known, somehow, prior to or independently of experience; in the first section of this chapter, I attempt to clarify this claim and describe some of the general features of a priori belief and knowledge. In the second section I argue, among other things, that a priori warrant is fallible and comes in degrees. I go on to consider an objection to the existence of a priori knowledge based on what has been called the causal requirement. I argue that there is no plausible form of the causal requirement that constitutes a good objection to the existence of a priori knowledge; along the way, I offer an argument for the conclusion that propositions cannot be concrete objects of any sort, and point out that it is quite possible to think of abstract objects as capable of standing in causal relations with us.

In this essay, I defend the compatibility of actualism – i.e., the view that there neither are, nor could have been, any nonexistent objects – and possible worlds. I begin by demonstrating how on the Canonical Conception of possible worlds one is committed to the idea that there are, or could have been, nonexistent objects. I then develop an actualist conception of possible worlds, properties, and essences. In particular, I deny that properties are set theoretical entities; something that the Canonical Conception endorses. Finally, I provide an actualist understanding of propositions such as there could have an object distinct from each object that actually exists – an understanding that does not commit one to belief in nonexistent objects.

The analogical position, as traditionally understood, is the claim that a person can inductively infer the existence of other minds from what he knows about his own mind and about physical objects. Of course this body of knowledge must not include such propositions about physical objects as "that human body over there is animated by a human mind," or "this automobile was designed by a human mind"; nor could my evidence for the existence of other minds be that I have it on the authority of some of the best minds in the country. The body of knowledge in question must not entail that there are any other minds. In "Induction and Other Minds" I used the term "total evidence" to refer to this body of knowledge, defining that term as follows

Paul Churchland argues that Plantinga’s evolutionary argument against naturalism is unsuccessful and so we need not accept its conclusion. In this paper, we respond to Churchland’s argument. After we briefly recapitulate Plantinga’s argument and state Churchland’s argument, we offer three objections to Churchland’s argument: (1) its first premise has little to recommend it, (2) its second premise is false, and (3) its conclusion is consistent with, and indeed entails, the conclusion of Plantinga’s argument.

Chapter 7 concluded with the claim that the Classical Argument for possible non‐existent objects depends on both the possibility of singular negative existentials and the Ontological Principle. The Ontological Principle is the principle that any world in which a singular proposition is true is one in which there is such a thing as its subject, or in which its subject has being if not existence. In this chapter, I show that the Ontological Principle is false and that whatever plausibility it enjoys is explained by the truth of a similar principle, namely, the Restricted Ontological Principle. Thus, the Classical Argument fails. Moreover, I give an account of how fictional names function in order to show that statements about fictional subjects, for example, ‘Othello is a Moor’, do not express predicative singular propositions.

I begin by introducing the ideas of possible worlds, books on worlds, and essential properties. A possible world is a broadly logically possible state of affairs that is maximal. Furthermore, for any possible world W and proposition p, let the book on W be the set S of propositions such that p is a member of S if W entails p. Finally, an object x has property P essentially if and only if x has P and has it in every world in which x exists. I use the above three concepts to give a sound argument for the conclusion that human persons are essentially immaterial.

I discuss three objections to essentialism. The first objection is from Gilbert Harman, who claims that because numbers can be identified or reduced to sets it follows that numbers cannot have essential properties. In the second objection, William Kneale argues for the conclusion that objects have essential properties only relative to a certain way of specifying or selecting the object. Kneale's argument suffers from a de re/de dicto confusion and the disambiguated reading of his argument is unsound. The third objection, Quine's mathematical cyclist, contains a similar confusion.

I clarify the notion of necessity that I will be examining in the book. In the first section, I claim that the relevant notion of necessity is ‘broad logical necessity’, which I distinguish from causal necessity, unrevisability and a proposition being self‐evident or a priori. In the second section, I distinguish between modality de dicto and modality de re. An assertion of modality de dicto predicates a modal property of another dictum or proposition, while a claim of modality de re asserts of an object that it possess a property either essentially or contingently. I conclude by examining the use of the de dicto/de re distinction in the works of Aristotle, St. Thomas Aquinas, G.E. Moore, and Norman Malcolm.

Chapter 6 is an attempt to show that the Theory of Worldbound Individuals —i.e. the theory that any object exists in exactly one possible world—is false, and that there's no good reason to deny that objects exist in more than one world. First, arguments that attempt to show that a denial of TWI entails a contradiction fail, and the so‐called Problem of Transworld Identity is no problem at all. Second, TWI should be rejected because it entails that all of an object's properties are essential to it. The defender of TWI may attempt to defend his view by adopting Counterpart Theory. I conclude by arguing that the Counterpart Theory is both semantically and metaphysically inadequate.

Chapter 7 explores the question: Are there or could there be, possible but non‐existent objects? In the first half of the chapter, I critically assess the claim that an applied semantics for modal logic commits us to the claim that there are non‐existent possible objects. I conclude that it does commit us to there being some possible world distinct from the actual world that contains some object distinct from anything that exists in the actual world; but it does not, however, commit us to the claim that there really are some things that do not exist. In the second half of the chapter, I develop a historically based argument for the conclusion that there are non‐existent possible objects, which I call the Classical Argument. Importantly, the Classical Argument presupposes that singular negative existentials are possible. I end the chapter by showing that certain objections to the possibility of singular negative existentials fail, and that such existentials are indeed possible.

I argue that each object has many essences. A property E is an essence of object x if and only if E is essential to x and in every possible world everything distinct from x has the complement of E essentially. I then elaborate on the nature of essences and examine the relationship between essences and proper names. My view is that John Stuart Mill was mistaken in his belief that proper names do not express properties. In fact, proper names express essences and I make use of this fact in addressing the famous problem of Hesperus and Phosphorus.