Much discussion about experimental philosophy and philosophical methodology has been framed in terms of the reliability of intuitions, and even when it has not been about reliability per se, it has been focused on whether intuitions meet whatever conditions they need to meet to be trustworthy as evidence. But really that question cannot be answered independently from the questions, evidence for what theories arrived at by what sorts of inferences? I will contend here that not just philosophy's sources of evidence, (...) but also its inferential resources, are in great need of closer examination. (shrink)

I reconstruct and critique two arguments Laurence BonJour has recently offered against skepticism about the a priori. While the arguments may provide anti-skeptical, internalist foundationalists with reason to accept the a priori, I show that neither argument provides sufficient reason for believing the more general conclusion that there is no rational alternative to accepting the a priori.

Some philosophical positions maintain that some aspect of reality depends on human practices, cognitive attitudes or sentiments. This paper presents a framework for understanding such positions in a way that renders them immune to a number of natural but allegedly devastating objections.

I present and defend (1) an account of ethical judgments as judgments about our reasons to feel specific motivationally laden attitudes, (2) an account of what an agent should do in terms of what would achieve ends that she has reason to be motivated to pursue, and (3) an account of an agent’s reasons for motivation (and thus action) in terms of the prescriptions of the most fundamental principles that guide her deliberations. Using these accounts, I explain the connection between (...) ethics and reasons for action, how ethical judgments are both descriptive and intrinsically motivating, and how ethical facts arise from facts about agents’ deliberations. (shrink)

I give a brief overview of Albert Casullo’s Essays on A Priori Knowledge and Justification (2012), followed by a summary of his diagnostic framework for evaluating accounts of a priori knowledge and a priori justification. I then discuss Casullo’s strategy for countering deficiency arguments against empiricism. A deficiency argument against empiricism can be countered by mounting a parallel argument against moderate rationalism that shows moderate rationalism to be defective in a similar way. I argue that a particular deficiency argument put (...) forth by George Bealer in “The Incoherence of Empiricism” (1992) can withstand a parallel challenge mounted by Casullo (2012, Ch.6). -/- I then consider Casullo’s preferred analysis of the concept of a priori justification, which identifies a belief’s being justified by some nonexperiential source as the feature by virtue of which it is justified a priori. On the analysis, an apriori-justfied belief that is justified to a degree that is sufficient for knowledge is not taken to be empirically indefeasible. I argue that Casullo could avail himself of an empirical indefeasibility requirement that is consistent with his minimal and fallibilist conception of a priori knowledge. Doing so would capture a feature of the concept of a priori knowledge that is of particular interest and significance. (shrink)

This paper offers an account of the a priori. According to this account, the fundamental notion is not that of a priori knowledge, or even of a priori justified belief, but a notion of an a priori justified inferential disposition. The rationality or justification of such a priori justified inferential dispositions is explained purely by some of the basic cognitive capacities that the thinker possesses, independently of any further experiences or other conscious mental states that the thinker happens to have (...) had. It is then shown how a priori justified inferences and beliefs can be explained on the basis of such a priori justified inferential dispositions. (shrink)

The practice of thought experimentation plays a central role in contemporary philosophical methodology. Many philosophers rely on thought experimentation as their primary and even sole procedure for testing theories about the natures of properties and relations. This test procedure involves entertaining hypothetical cases in imaginative thought and then undergoing intuitions about the distribution of properties and relations in them. A theory’s comporting with an intuition is treated as evidence in favour of it; but a clash is treated as evidence against (...) the theory and may even be regarded as falsifying it. -/- The epistemic power of thought experimentation is mysterious. How can experiments carried out within the mind enable us to discover truths about the natures of properties and relations like knowledge, causation, personal identity, reference, meaning, consciousness, beauty, justice, morality, and free will? This epistemological challenge is urgent, but a model of philosophical thought experimentation would seem to be a necessary propaedeutic to any serious discussion of it. An adequate model would make the relevant test procedure explicit, thereby assisting in the identification of points of potential epistemic vulnerability. -/- In this monograph I advance the propaedeutical model-building work already done by Timothy Williamson, Anna-Sara Malmgren, and Jonathan Ichikawa and Benjamin Jarvis. Following the lead of these philosophers, I focus on a single Gettier-style thought experiment and the problem of identifying the real content of the Gettier intuition. My first contribution is to establish the inadequacy of all of the existing models. Each of them, I argue, fails to solve the content problem. It emerges from my discussion, however, that Ichikawa and Jarvis’s truth in fiction approach holds out the prospect of a solution. -/- My second contribution is to develop and defend a new way of implementing the general idea behind the truth in fiction approach. The model I put forward does a better overall job of modelling Gettier-style thought experiments than any of the existing models. It has none of the defects which render those models inadequate and Iam unable to find any major defects peculiar to it. This should make us feel confident that my model is adequate. Moreover, since the Gettier-style thought experiment I focus on is paradigmatic, we should also feel confident that my model will generalise naturally to other philosophical thought experiments. (shrink)

Does rationality require logical omniscience? Our best formal theories of rationality imply that it does, but our ordinary evaluations of rationality seem to suggest otherwise. This paper aims to resolve the tension by arguing that our ordinary evaluations of rationality are not only consistent with the thesis that rationality requires logical omniscience, but also provide a compelling rationale for accepting this thesis in the first place. This paper also defends an account of apriori justification for logical beliefs that is designed (...) to explain the rational requirement of logical omniscience. On this account, apriori justification for beliefs about logic has its source in logical facts, rather than psychological facts about experience, reasoning, or understanding. This account has important consequences for the epistemic role of experience in the logical domain. In a slogan, the epistemic role of experience in the apriori domain is not a justifying role, but rather an enabling and disabling role. (shrink)

What I will call “the deviant logician objection” [DLO] is one line of attack against the common and compelling tenet that our justification for logical truths is grounded in our understanding of their constituent concepts. This objection seeks to undermine the possibility of any deep constitutive connection, in the epistemology of logic, between understanding and justification. I will consider varieties of the deviant logician objection developed by Horwich and by Williamson. My thesis is that while the deviant logician objection falls (...) short of proving that this traditional tenet must be rejected, nonetheless it serves to bolster some important refinements. (shrink)

This paper aims to clarify a debate on philosophical method, and to give a probabilistic argument vindicating armchair philosophy under a wide range of plausible assumptions. The use of intuitions by so-called armchair philosophers has been criticized on empirical grounds. The debate between armchair philosophers and their empirical critics would benefit from greater clarity and precision in our understanding of what it takes for intuition-based approaches to philosophy to make sense. This paper discusses a set of rigorous, probability-based tools for (...) determining what we can and cannot learn from intuitions in various conditions. These tools can tell us whether beliefs can be justified by armchair practices, and what empirical findings would have to show to undermine the use of intuitions in philosophy. Using these tools, the paper shows that armchair philosophy makes sense in a broad range of situations, and that it is quite plausible that we are in those situations at the moment. (shrink)

A large portion of philosophy done in the Western analytic tradition attempts to provide conceptual analyses which are tested by examples that elicit intuitions. These intuitions are, in turn, used as evidence either for or against a given analysis. In recent years, there has been much discussion of the uses of intuitions from empirically minded philosophers and psychologists. The basic strategy is to discover empirically how “normal” folks think about certain topics in philosophy. This application of folk intuitions to philosophy (...) branches into roughly two basic approaches. The first is an attempt to show that in given domains, folk intuitions are not very reliable sources of evidence; hence, we have good reason to think that philosophers' intuitions are also not reliable sources of evidence in that domain. The second approach attempts to determine what folk concepts are. Once folk concepts are analyzed, they are then argued to be relevant to philosophical debates. My guiding question for this dissertation is the following one: Why should philosophers care about folk intuitions? One answer is that we should want some philosophical analyses to be grounded in everyday concepts. I argue that there are presently no adequate a priori arguments for the reliability of philosophical intuitions in some philosophically relevant areas. Whether intuitions are reliable enough to ground philosophical analyses is an empirical question. I review four domains where ordinary concepts have been argued to ground philosophical theorizing: (1) epistemology, (2) ethics, (3) free will, and (4) action theory. I argue that the available evidence suggests that we should be skeptical of intuitions in philosophy—but that skepticism does not entail radical skepticism. That is, the empirical studies reveal a wide variety of results which on the surface indicate that intuitions are not reliable (e.g., order effects or framing effects). However, I argue that these seeming instabilities are actually the results of stable differences in different groups of people. Hence, I argue that intuitions are stable in a surprising way—that different groups of people have stable intuitions. This intuition stability, while not the kind of monolithic stability many philosophers might desire, is argued to be sufficient to ground philosophical analyses in these domains. (shrink)

In this paper, I argue that, contrary to common opinion, a counterexample against a philosophical theory does not amount to conclusive evidence against that theory. Instead, the method of counterexamples allows for the derivation of a disjunction, i.e., ‘either the theory is false or an auxiliary assumption is false’, not a negation of the target theory. This is so because, whenever the method of counterexamples is used in an attempt to refute a philosophical theory, there is a crucial auxiliary assumption (...) that needs to be taken into account. The auxiliary assumption is that making intuitive judgments in response to hypothetical cases about the subject matter in question (e.g., knowledge or proper names) is a good method for finding out truths about that subject matter. Without good reasons to think that this assumption is warranted, the negation of a philosophical theory whose content is alleged to be in conflict with the content of an intuition cannot be justifiably derived using an argument that employs the method of counterexamples. (shrink)

Jonas Olson presents a critical survey of moral error theory, the view that there are no moral facts and so all moral claims are false. Part I explores the historical context of the debate; Part II assesses J. L. Mackie's famous arguments; Part III defends error theory against challenges and considers its implications for our moral thinking.

Empiricist philosophers like Carnap invoked analyticity in order to explain a priori knowledge and necessary truth. Analyticity was “truth purely in virtue of meaning”. The view had a deflationary motivation: in Carnap’s proposal, linguistic conventions alone determine the truth of analytic sentences, and thus there is no mystery in our knowing their truth a priori, or in their necessary truth; for they are, as it were, truths of our own making. Let us call this “Carnapian conventionalism”, conventionalismC and cognates for (...) short. This conventionalistC explication of the a priori has been the target of sound criticisms. Arguments like Quine’s in “Truth by Convention” are in our view decisive: the truth of conventionalismC requires that the class of logical truths and logical validities be reductively accounted for as conventionally established; however, no such reduction is forthcoming, because logic is needed to generate the entire class from any given set of conventions properly so-called. Granted that conventionalismC is untenable, we want to take issue with a different, usually made criticism. Although the argument uncovers some difficulties for the way conventionalist claims are defended by some of its advocates, we will try to show that it fails. The criticism thus stands in the way of a proper appreciation of why the Carnapian account of the a priori is not correct. We will try to illustrate this by showing that the criticism we will dispute would dispose of conventionalist claims not only regarding philosophically problematic cases – logical and mathematical truths –, but also regarding cases for which they have some prima facie plausibility. One such case is that of truths that follow from mere abbreviations, “nominal” definitions; ‘someone is a bachelor if and only if he is an unmarried adult male’ can serve at this point for illustration. We will try to articulate a clear sense in which the contents of assertion such as this can be truths by convention. We do not need to prove that a conventionalist claim is true in those cases; it is enough for us to show that it is intelligible, for the arguments we will confront question even this. (shrink)

The purpose of this thesis is to demonstrate that metaphysics is a necessary discipline -- necessary in the sense that all areas of philosophy, all areas of science, and in fact any type of rational activity at all would be impossible without a metaphysical background or metaphysical presuppositions. Because of the extremely strong nature of this claim, it is not possible to put forward a very simple argument, although I will attempt to construct one. A crucial issue here is what (...) metaphysics in fact is -- the nature of metaphysics. The conception of metaphysics which I support could be called Aristotelian, as opposed to Kantian: metaphysics is the first philosophy and the basis of all other philosophical and scientific inquiry. I will argue that this is indeed the most plausible conception of metaphysics. (shrink)

Central elements of W. V. Quine’s epistemology are widely and deeply misunderstood, including the following. He held from first to last that our evidence consists of the stimulations of our sense organs, and of our observations, and of our sensory experiences; meeting the interpretive challenge this poses is a sine qua non of understanding his epistemology. He counted both “This is blue” and “This looks blue” as observation sentences. He took introspective reports to have a high degree of certainty. He (...) endorsed outright Hume’s “skeptical” argument concerning induction. His naturalized epistemology is simply naturalistic, or scientific, epistemology stripped of the project of rational reconstruction, and is thoroughly normative. Quine was unconditionally a scientific philosopher who took our theories to be answerable ultimately to our perceptual experiences (sensations)—and conditionally an empiricist, empiricism being a scientific theory that has no competitors worthy of the name. I attempt to make all of this clear, and conclude by offering a concise formulation of his epistemology. (shrink)

In his book In Defense of Pure Reason Laurence BonJour proposed an account of a priori justification which essentially refers to so-called rational insights. Unfortunately, the reader is not equipped with a substantial answer to the question what such rational insights exactly are. And moreover, he is told that this is not an in any way decisive shortcoming of BonJour’s account of a priori justification — at least not a shortcoming which should motivate us to abandon his account. In order (...) to support this thesis, BonJour refers to an analogy between the case of rational insights and the case of consciousness. He points out that we would not give up the use of the notion of consciousness, in spite of the fact that today there is still no satisfying answer to the question what consciousness exactly is. I will argue that the analogy BonJour refers to is in fact a persuasive one and can help him as well as other proponents of the rational-insight account to deal with some prominent objections. But taking the analogy seriously does consequently mean to undermine a favourite rationalist’s thesis: the autonomy claim. I conclude that the rationalist is confronted with a dilemma; he simply cannot have it both ways. (shrink)

In this paper I will argue that this entire dialectic is somewhat misguided. The mental states which are generally assumed to fall under the category of ‘intuition’ likely comprise a highly heterogeneous group; from the point of view of psychology or of neuroscience, in fact, ‘intuitions’ appear to be generated by several fundamentally different sorts of mental processes. If this is correct, then the term ‘intuition’ may simply carve things too broadly. I will argue that it is a mistake to (...) focus on the ‘reliability of intuition’; empirical evidence suggests that the reliability of one type of intuition may tell us next to nothing about the reliability of other types. Rather than debating the evidential status of intuition as a whole, philosophers interested in methodology would do well to focus their investigations much more narrowly. (shrink)

Originally published in 1991, The Laboratory of the Mind: Thought Experiments in the Natural Sciences, is the first monograph to identify and address some of the many interesting questions that pertain to thought experiments. While the putative aim of the book is to explore the nature of thought experimental evidence, it has another important purpose which concerns the crucial role thought experiments play in Brown’s Platonic master argument.In that argument, Brown argues against naturalism and empiricism (Brown 2012), for mathematical Platonism (...) (Brown 2008), and from the Platonist-friendly, abstract universals posited by the Dretske-Tooley-Armstrong (DTA) account of the laws of nature to a more general, physical Platonism. The Laboratory of the Mind is where he takes this final step. (shrink)

In this paper, I present counterexamples to the evidence thesis, the thesis that S knows that p at t only if S believes that p on the basis of evidence at t. The outline of my paper is as follows. In section 1, I explain the evidence thesis and make clear what a successful counterexample to the evidence thesis will look like. In section 2, I show that instances of non-occurrent knowledge are counterexamples to the evidence thesis. At the end (...) of section 2, I consider the primary thesis of my paper — that the evidence thesis is false — to be successfully defended. In section 3, I consider three variations of the evidence thesis. The first variation restricts the evidence thesis to occurrent knowledge; the second requires for knowledge that one’s belief could be based on evidence; and the third requires for knowledge that the belief was based on evidence at a suitable prior time. The secondary thesis of this paper is that these variations are also subject to serious objections. (shrink)

Intuitions play an important role in contemporary philosophy. It is common for theories in epistemology, morality, semantics and metaphysics to be rejected because they are inconsistent with a widely and firmly held intuition. Our goal in this paper is to explore the role of epistemic intuitions in epistemology from a naturalistic perspective. Here is the question we take to be central: (Q) Ought we to trust our epistemic intuitions as evidence in support of our epistemological theories? We will understand this (...) question as employing an epistemic ‘ought’ – insofar as we aim at developing a correct epistemological theory, ought we to trust our epistemic intuitions as evidence for or against our epistemological theories? As it stands, (Q) needs further clarification. Whether something is trustworthy is relative to what (a) what it is and (b) what we’re asking it to do. Sam might trust Marie but not George to care for his children, while he might trust both to care for his pet fish. So in order to address (Q), we first need to explore two questions: What are epistemic intuitions? And what sort of epistemological theories do we want? We will take up each of these questions in the following sections. (shrink)

Paul Benacerraf’s argument that mathematical realism is apparently incompatible with mathematical knowledge has been widely thought to also show that a priori knowledge in general is problematic. Although many philosophers have rejected Benacerraf’s argument because it assumes a causal theory of knowledge, some maintain that Benacerraf nevertheless put his finger on a genuine problem, even though he didn’t state the problem in its most challenging form. After diagnosing what went wrong with Benacerraf’s argument, I argue that a new, more challenging, (...) version of Benacerraf’s problem can be constructed. The new version—what I call the Defeater Version—of Benacerraf’s problem makes use of a no-defeater condition on knowledge and justification. I conclude by arguing that the best way to avoid the problem is to construct a theory of how a priori judgments reliably track the facts. I also suggest four different kinds of theories worth pursuing. (shrink)

Defenders of pragmatic encroachment in epistemology (or what I call practicalism) need to address two main problems. First, the view seems to imply, absurdly, that knowledge can come and go quite easily—in particular, that it might come and go along with our variable practical interests. We can call this the stability problem. Second, there seems to be no fully satisfying way of explaining whose practical interests matter. We can call this the “whose stakes?” problem. I argue that both problems can (...) be addressed in roughly the same terms. More exactly, I argue that by first clarifying the whose stakes? problem an answer to the stability problem naturally falls out. (shrink)

An argument is epistemically self-defeating when either the truth of an argument’s conclusion or belief in an argument’s conclusion defeats one’s justification to believe at least one of that argument’s premises. Some extant defenses of the evidentiary value of intuition have invoked considerations of epistemic self-defeat in their defense. I argue that there is one kind of argument against intuition, an unreliability argument, which, even if epistemically self-defeating, can still imply that we are not justified in thinking intuition has evidentiary (...) value. (shrink)

Many philosophers accept a view – what I will call the intuition picture – according to which intuitions are crucial evidence in philosophy. Recently, Williamson has argued that such views are best abandoned because they lead to a psychologistic conception of philosophical evidence that encourages scepticism about the armchair judgements relied upon in philosophy. In this paper I respond to this criticism by showing how the intuition picture can be formulated in such a way that: it is consistent with a (...) wide range of views about not only philosophical evidence but also the nature of evidence in general, including Williamson's famous view that E = K; it can maintain the central claims about the nature and role of intuitions in philosophy made by proponents of the intuition picture; it does not collapse into Williamson's own deflationary view of the nature and role of intuitions in philosophy; and it does not lead to scepticism. (shrink)

Adequate epistemic justification is best conceived as the appearance, over time, of knowledge to the subject. ‘Appearance’ is intended literally, not as a synonym for belief. It is argued through consideration of examples that this account gets the extension of ‘adequately justified belief’ at least roughly correct. A more theoretical reason is then offered to regard justification as the appearance of knowledge: If we have a knowledge norm for assertion, we do our best to comply with this norm when we (...) express as assertions only beliefs that appear to us to be knowledge. If we are doing our best, there is little point in further sanctions. So a norm of knowledge for assertion would lead to a secondary norm of justified belief as the appearance of knowledge, marking a point at which our assertions may be corrected but should not be blamed. (shrink)

When it comes to epistemic normativity, should we take the good to be prior to the right? That is, should we ground facts about what we ought and ought not believe on a given occasion in facts about the value of being in certain cognitive states (such as, for example, the value of having true beliefs)? The overwhelming answer among contemporary epistemologists is “Yes, we should.” This essay argues to the contrary. Just as taking the good to be prior to (...) the right in ethics often leads one to sanction implausible trade-offs when determining what an agent should do, so too, this essay argues, taking the good to be prior to the right in epistemology leads one to sanction implausible trade-offs when determining what a subject should believe. Epistemic value—and, by extension, epistemic goals—are not the explanatory foundation upon which all other normative notions in epistemology rest. (shrink)

A self-fulfilling fallacy (SFF) is a fallacious argument whose conclusion is that the very fallacy employed is an invalid or otherwise illegitimate inferential procedure. This paper discusses three different ways in which SFF’s might serve to justify their conclusions. SFF’s might have probative value as honest and straightforward arguments, they might serve to justify the premise of a meta-argument or, following a point made by Roy Sorensen, they might provide a non-inferential basis for accepting their conclusion. The paper concludes with (...) an assessment of the relative merits of these proposals. (shrink)

The distinction between a priori and a posteriori knowledge has been the subject of an enormous amount of discussion, but the literature is biased against recognizing the intimate relationship between these forms of knowledge. For instance, it seems to be almost impossible to find a sample of pure a priori or a posteriori knowledge. In this paper, it will be suggested that distinguishing between a priori and a posteriori is more problematic than is often suggested, and that a priori and (...) a posteriori resources are in fact used in parallel. We will define this relationship between a priori and a posteriori knowledge as the bootstrapping relationship. As we will see, this relationship gives us reasons to seek for an altogether novel definition of a priori and a posteriori knowledge. Specifically, we will have to analyse the relationship between a priori knowledge and a priori reasoning , and it will be suggested that the latter serves as a more promising starting point for the analysis of aprioricity. We will also analyse a number of examples from the natural sciences and consider the role of a priori reasoning in these examples. The focus of this paper is the analysis of the concepts of a priori and a posteriori knowledge rather than the epistemic domain of a posteriori and a priori justification. (shrink)

My purpose in this paper is to examine the role of intuition in conceptual analysis and to assess whether that role can be parlayed into a plausible defense of a priori knowledge. The focus of my investigation is George Bealer’s attempt to provide such a defense. I argue that Bealer’s account of intuition and its evidential status faces three problems. I go on to examine the two primary arguments that Bealer offers against empiricism: the Starting Points Argument and the Argument (...) from Epistemic Norms. I argue that the Starting Points Argument fails because Bealer fails to show that intuitions are a priori evidence and that the Argument from Epistemic Norms fails because it is open to the Stalemate Problem. I conclude by offering an alternative approach to defending the a priori status of intuitions that avoids the Stalemate Problem. The alternative approach highlights the role of empirical investigation in defending the a priori. (shrink)

In this paper I assume that we have some intuitive knowledge—i.e. beliefs that amount to knowledge because they are based on intuitions. The question I take up is this: given that some intuition makes a belief based on it amount to knowledge, in virtue of what does it do so? We can ask a similar question about perception. That is: given that some perception makes a belief based on it amount to knowledge, in virtue of what does it do so? (...) A natural idea about perception is that a perception makes a belief amount to knowledge in part by making you sensorily aware of the concrete objects it is about. The analogous idea about intuition is that an intuition makes a belief amount to knowledge in part by making you intellectually aware of the abstract objects it is about. I expand both ideas into fuller accounts of perceptual and intuitive knowledge, explain the main challenge to this sort of account of intuitive knowledge (i.e. the challenge of making sense of intellectual awareness), and develop a response to it. (shrink)

Deductive reasoning is the kind of reasoning in which, roughly, the truth of the input propositions (the premises) logically guarantees the truth of the output proposition (the conclusion), provided that no mistake has been made in the reasoning. The premises may be propositions that the reasoner believes or assumptions that the reasoner is exploring. Deductive reasoning contrasts with inductive reasoning, the kind of reasoning in which the truth of the premises need not guarantee the truth of the conclusion.

We think of logic as objective. We also think that we are reliable about logic. These views jointly generate a puzzle: How is it that we are reliable about logic? How is it that our logical beliefs match an objective domain of logical fact? This is an instance of a more general challenge to explain our reliability about a priori domains. In this paper, I argue that the nature of this challenge has not been properly understood. I explicate the challenge (...) both in general and for the particular case of logic. I also argue that two seemingly attractive responses – appealing to a faculty of rational insight or to the nature of concept possession – are incapable of answering the challenge. (shrink)

I argue that you can have a priori knowledge of propositions that neither are nor appear necessarily true. You can know a priori contingent propositions that you recognize as such. This overturns a standard view in contemporary epistemology and the traditional view of the a priori, which restrict a priori knowledge to necessary truths, or at least to truths that appear necessary.

If we add as an extra premise that the agent does know H, then it is possible for her to know E — H, we get the conclusion that the agent does not really know H. But even without that closure premise, or something like it, the conclusion seems quite dramatic. One possible response to the argument, floated by both Descartes and Hume, is to accept the conclusion and embrace scepticism. We cannot know anything that goes beyond our evidence, so (...) we do not know very much at all. This is a remarkably sceptical conclusion, so we should resist it if at all possible. A more modern response, associated with externalists like John McDowell and Timothy Williamson, is to accept the conclusion but deny it is as sceptical as it first appears. The Humean argument, even if it works, only shows that our evidence and our knowledge are more closely linked than we might have thought. Perhaps that’s true because we have a lot of evidence, not because we have very little knowledge. There’s something right about this response I think. We have more evidence than Descartes or Hume thought we had. But I think we still need the idea of ampliative knowledge. It stretches the concept of evidence to breaking point to suggest that all of our knowledge, including knowledge about the future, is part of our evidence. So the conclusion really is unacceptable. Or, at least, I think we should try to see what an epistemology that rejects the conclusion looks like. (shrink)

In this paper, I consider an argument for the claim that any satisfactory epistemology of mathematics will violate core tenets of naturalism, i.e. that mathematics cannot be naturalized. I find little reason for optimism that the argument can be effectively answered.

Alberto Coffa used the phrase "the Copernican turn in semantics" to denote a revolutionary transformation of philosophical views about the connection between the meanings of words and the acceptability of sentences and arguments containing those words. According to the new conception resulting from the Copernican turn, here called "the Copernican view", rules of use are constitutive of the meanings of words. This view has been linked with two doctrines: (A) the instances of meaning-constitutive rules are analytically and a priori true (...) or valid; (B) to grasp a meaning is to accept its rules. The pros and cons of different versions of the Copernican view, ascribable to Wittgenstein, Carnap, Gentzen, Dummett, Prawitz, Boghossian and other authors, will be weighed. A new version will be proposed, which implies neither (A) nor (B). (shrink)

How ought we to go about forming and revising our beliefs, arguing and debating our reasons, and investigating our world? If those questions constitute normative epistemology, then I am interested here in normative metaepistemology: the investigation into how we ought to go about forming and revising our beliefs about how we ought to go about forming and revising our beliefs -- how we ought to argue about how we ought to argue. Such investigations have become urgent of late, for the (...) methodology of epistemology has reached something of a crisis. For analytic epistemology of the last half-century has relied overwhelmingly on intuitions,1 and a growing set of arguments and data has begun to call this reliance on intuition seriously into question (e.g., Weinberg, Nichols, and Stich 2001; Nichols, Stich, and Weinberg 2003; Cummins 1998). Although that method has not been entirely without defenders (BonJour 1998; Bealer 1996; Jackson 1998; Sosa forthcoming; Weatherson 2003), these defenses have not generally risen to the specific challenges leveled by the anti-intuitionist critics. In particular, the critics have attacked specific ways of deploying intuitions, and the defenders have overwhelmingly responded with in-principle defenses of the cogency of appealing to intuition. An analogy here would be someone’s responding to arguments alleging systematic.. (shrink)

I defend the principle of Phenomenal Conservatism, on which appearances of all kinds generate at least some justification for belief. I argue that there is no reason for privileging introspection or intuition over perceptual experience as a source of justified belief; that those who deny Phenomenal Conservatism are in a self-defeating position, in that their view cannot be both true and justified; and that thedemand for a metajustification for Phenomenal Conservatism either is an easily met demand, or is an unfair (...) or question-begging one. (shrink)

Laurence BonJour’s In Defense of Pure Reason is rich and challenging. It offers a tightly integrated attack on empiricism and defense of rationalism. The tight texture of argument makes it difficult to isolate and assess specific aspects of the book in a brief discussion. My goal is to examine the role of experience in BonJour’s conception of a priori justification.

This paper argues that a priori justification is, in principle, compatible with naturalism—if the a priori is understood in a way that is free of the inessential properties that, historically, have been associated with the concept. I argue that empirical indefeasibility is essential to the primary notion of the a priori ; however, the indefeasibility requirement should be interpreted in such a way that we can be fallibilist about apriori-justified claims. This fallibilist notion of the a priori accords with the (...) naturalist’s commitment to scientific methodology in that it allows for apriori-justified claims to be sensitive to further conceptual developments and the expansion of evidence. The fallibilist apriorist allows that an a priori claim is revisable in only a purely epistemic sense. This modal claim is weaker than what is required for a revisability thesis to establish empiricism, so fallibilist apriorism represents a distinct position. (shrink)

Something about this argument sounds funny. As we’ll see, though, it takes some care to identify exactly what Moore has done wrong. Iwill assume that Moore knows premise (2) to be true. One could inquire into how he knows it, and whether that knowledge can be defeated; but Iwon’t. I’ll focus instead on what epistemic relations Moore has to premise (1) and to his conclusion (3). It may matter which epistemic relations we choose to consider. Some philosophers will diagnose Moore’s (...) argument using Contextualist machinery. They’ll say. (shrink)

My goal in this paper is to explain what ethical naturalism is, to locate the pivotal issue between naturalists and non-naturalists, and to motivate taking naturalism seriously. I do not aim to establish the truth of naturalism nor to answer the various familiar objections to it. But I do aim to motivate naturalism sufficiently that the attempt to deal with the objections will seem worthwhile. I propose that naturalism is best understood as the view that the moral properties are natural (...) in the sense that they are empirical. I pursue certain issues in the understanding of the empirical. The crux of the matter is whether any synthetic proposition about the instantiation of a moral property is strongly a priori in that it does not admit of empirical evidence against it. I propose an argument from epistemic defeaters that, I believe, undermines the plausibility of a priorism in ethics and supports the plausibility of naturalism. (shrink)

The original proof of the four-color theorem by Appel and Haken sparked a controversy when Tymoczko used it to argue that the justification provided by unsurveyable proofs carried out by computers cannot be a priori. It also created a lingering impression to the effect that such proofs depend heavily for their soundness on large amounts of computation-intensive custom-built software. Contra Tymoczko, we argue that the justification provided by certain computerized mathematical proofs is not fundamentally different from that provided by surveyable (...) proofs, and can be sensibly regarded as a priori. We also show that the aforementioned impression is mistaken because it fails to distinguish between proof search (the context of discovery) and proof checking (the context of justification). By using mechanized proof assistants capable of producing certificates that can be independently checked, it is possible to carry out complex proofs without the need to trust arbitrary custom-written code. We only need to trust one fixed, small, and simple piece of software: the proof checker. This is not only possible in principle, but is in fact becoming a viable methodology for performing complicated mathematical reasoning. This is evinced by a new proof of the four-color theorem that appeared in 2005, and which was developed and checked in its entirety by a mechanical proof system. (shrink)