In this paper, we present a dialectical argument for a priori skepticism (i.e. the thesis that we can be skeptical about a priori knowledge). Then, we propose a framework that combines elements from inferential contextualism and logical conventionalism to offer a weak transcendental argument against a priori skepticism.

This paper contains replies to comments on the author's paper "A Priori Knowledge and the Scope of Philosophy." Several points in the argument of that paper are given further clarification: the notion of our standard justificatory procedure, the notion of a basic source of evidence, and the doctrine of modal reliabilism. The reliability of intuition is then defended against Lycan's skepticism and a response is given to Lycan's claim that the scope of a priori knowledge does not (...) include philosophically central topics such as the nature of consciousness. Next a counterfactual account of intuitions proposed by Sosa is criticized. Finally, in response to certain questions raised by Sosa, the explanation of the evidential status of intuition offered in the original paper receives further elaboration. (shrink)

Joel Pust has recently challenged the Thomas Reid-inspired argument against the reliability of the a priori defended by Alvin Plantinga, Nicholas Wolterstorff, William Alston, and Michael Bergmann. The Reidian argument alleges that the Cartesian insistence on the primacy of a priori rationality and subjective sensory experience as the foundations of epistemic justification is unwarranted because the same kind of global skeptical scenario that Cartesians recognize as challenging the legitimacy of perceptual beliefs about the external world also undermine the (...) reliability of a priori rationality. In reply, Pust contends that some a priori propositions are beyond doubt and that fact can be used to support the overall reliability of reason. This paper challenges Pust’s argument. I argue that while Pust successfully undermines a radical skeptical view of reason, he does not refute a more modest skepticism. I conclude with some suggestions for Cartesian a priorists. (shrink)

Hillary Putnam has famously argued that we can know that we are not brains in a vat because the hypothesis that we are is self-refuting. While Putnam's argument has generated interest primarily as a novel response to skepticism, his original use of the brain in a vat scenario was meant to illustrate a point about the "mind/world relationship." In particular, he intended it to be part of an argument against the coherence of metaphysical realism, and thus to be part (...) of a defense of his conception of truth as idealized rational acceptability. Putnam's conclusions about the scenario are, however, actually out of line with central and plausible aspects of his own account of the relationship between our minds and the world. Reflections on semantics give us no compelling reason to suppose that claims like "I am a brain in a vat" could not turn out to be true. (shrink)

Considering three philosophers – Ghazali , Hume, and Kant – we perceive that they were at grips with skepticism and each had a different attitude towards it. While Hume remains in a skeptical sphere, Ghazali and Kant offer solutions for skepticism, although their solutions differ largely. Criticizing Aristotle’s view on essential necessity, Ghazali expands Avicenna’s emphasis on experimentation and, in effect, negates the necessary relation between cause and effect. Ghazali preceded Hume in this regard for some 6 centuries (...) and put forward Hume’s main idea. In order to overcome skepticism, Kant appealed to rationality and it’s a priori backgrounds, while Ghazali put forward God’s will and put the emphasis on the inner direct experience. It will be argued that God’s deeds, rationality and faith should be compatible in principle. (shrink)

Many philosophers have found in Hume’s skeptical doubts concerning the operations of the understanding the materials for an argument that generalizes from induction to other domains, like our beliefs in the external world, other minds, and the past. This chapter offers a novel reconstruction of that argument and identifies the principles that are responsible for its capacity to generalize beyond induction. Next, it presents a classical reading of Hume’s skeptical solution and shows that Crispin Wright’s entitlement theory is close in (...) spirit to it. After that, it develops two objections to entitlement theory: it relies on the truth of deeply contingent propositions that are not a priori rational, and it does not manage to redefine the concept of epistemic rationality while offering an effective anti-skeptical response. The chapter concludes with a constructive suggestion: some passages that support a non-classical reading of Hume’s positive views on induction offer the materials to reject the steps of the skeptical argument that cause trouble for entitlement theory. (shrink)

Less discussed than Hume’s skepticism about what grounds there could be for projecting empirical hypotheses is his concern with a skeptical regress that he thought threatened to extinguish any belief when we reflect that our reasoning is not perfect. The root of the problem is the fact that a reflection about our reasoning is itself a piece of reasoning. If each reflection is negative and undermining, does that not give us a diminution of our original belief to nothing? It (...) requires much attention to detail, we argue, to determine whether or not there is a skeptical problem in this neighborhood. Consider that if we subsequently doubt a doubt we had about our reasoning, that would suggest a restoration of some of the force of our original belief. We would then have instead of runaway skepticism an alternating sequence of pieces of skeptical reasoning that cancel each others’ effects on our justification in the original proposition, at least to some degree. We will argue that the outcome of the sequence of reflections Hume is imagining depends on information about a given case that is not known a priori. We conclude this from the fact that under three precise, explanatory, and viable contemporary reconstructions of what this kind of reasoning about reasoning could be like and how it has the potential to affect our original beliefs, a belief-extinguishing regress is not automatic or necessary. (shrink)

In this paper I will draw attention to an important route to external world skepticism, which I will call confidence skepticism. I will argue that we can defang confidence skepticism (though not a meeker ‘argument from might’ which has got some attention in the 20th century literature on external world skepticism) by adopting a partially psychologistic answer to the problem of priors. And I will argue that certain recent work in the epistemology of mathematics and logic (...) provides independent support for such psychologism. (shrink)

Moral skeptics maintain that we do not have moral knowledge. Traditionally they haven’t argued via skeptical hypotheses like those provided by perceptual skeptics about the external world, such as Descartes’ deceiving demon. But some believe this can be done by appealing to hypotheses like moral nihilism. Moreover, some claim that skeptical hypotheses have special force in the moral case. But I argue that skeptics have failed to specify an adequate skeptical scenario, which reveals a general lesson: such arguments are not (...) a promising avenue for moral skeptics to take. They’re ultimately weaker when applied to morality compared to perception. (shrink)

In his early writings, Kant says that the solution to the puzzle of how morality can serve as a motivating force in human life is nothing less than the “philosophers’ stone.” In this dissertation I show that for years Kant searched for the philosophers’ stone in the concept of “respect” (Achtung), which he understood as the complex effect practical reason has on feeling. -/- I sketch the history of that search in Chapters 1-2. In Chapter 3 I show that Kant’s (...) analysis in Groundwork I is incomplete because it does not explain how respect functions as a feeling in motivating choice. In Chapter 4 I argue that Kant’s subsequent attempt to sidestep this explanation in Groundwork III is unsuccessful, and that his position remains open to a skeptical threat. The argument in the second Critique, which I reconstruct in Chapters 5-6, overcomes this threat, and in doing so explains how the feeling of respect is both painful and pleasurable. -/- In the course of defending these claims, I provide an alternative reading of the shift in Kant’s ethical project from the Groundwork of 1785 to the second Critique of 1788 Against a common view in the literature, I argue that the shift does not concern the direction of Kant’s deduction (from freedom to morality, or morality to freedom); rather, it concerns his view of human sensibility and the resources he thinks we have to make our practical self-understanding intelligible. In the second Critique, I argue, Kant develops a novel approach to moral feeling from the perspective of the human agent; and this in turn clears room in his ethics for a new kind of a priori knowledge—namely, knowledge of what the activity of practical reason must feel like. By way of conclusion, I offer a few reasons for why the form of Kant’s argument in the second Critique is still relevant today, as it shows why we can only address moral skepticism from a first-personal perspective. (shrink)

The deduction of categories in the 1781 edition of the Critique of the Pure Reason (A Deduction) has “two sides”—the “objective deduction” and the “subjective deduction”. Kant seems ambivalent about the latter deduction. I treat it as a significant episode of Kant’s thinking about categories that extended from the early 1770s to around 1790. It contains his most detailed answer to the question about the origin of categories that he formulated in the 1772 letter to Marcus Herz. The answer is (...) that categories are generated a priori through a kind of intellectual “epigenesis”. This account leaves unexplained why precisely such and such categories should be generated. While this observation caused Kant to worry about the hypothetical status of the subjective deduction in 1781, he would come to acquiesce in the recognition that the ground of the possibility of categories is itself inscrutable. I call this his “methodological skepticism”. (shrink)

The problem of skepticism is often understood as a paradox: a valid argument with plausible premises whose conclusion is that we lack justification for perceptual beliefs. Typically, this conclusion is deemed unacceptable, so a theory is offered that posits conditions for justification on which some premise is false. The theory defended here is more general, and explains why the paradox arises in the first place. Like Strawson’s (Introduction to logical theory, Wiley, New York, 1952) “ordinary language” approach to induction, (...) the theory posits something built into the very notion of justification: it is loaded with a bias towards the proposition that we are not massively deceived. Beyond the paradox, remaining skeptical problems consist of metaphysical and practical questions: whether we are massively deceived, or why we should use our loaded notion rather than some other. Such challenges have pro- found epistemological significance, but they are not problems that an a priori theory of justification can solve. (shrink)

This dissertation is concerned with two of the largest questions that we can ask about the nature of physical reality: first, whether physical reality begin to exist and, second, what criteria would physical reality have to fulfill in order to have had a beginning? Philosophers of religion and theologians have previously addressed whether physical reality began to exist in the context of defending the Kal{\'a}m Cosmological Argument (KCA) for theism, that is, (P1) everything that begins to exist has a cause (...) for its beginning to exist, (P2) physical reality began to exist, and, therefore, (C) physical reality has a cause for its beginning to exist. While the KCA has traditionally been used to argue for God's existence, the KCA does not mention God, has been rejected by historically significant Christian theologians such as Thomas Aquinas, and raises perennial philosophical questions -- about the nature and history of physical reality, the nature of time, the nature of causation, and so on -- that should be of interest to all philosophers and, perhaps, all humans. While I am not a religious person, I am interested in the questions raised by the KCA. In this dissertation, I articulate three necessary conditions that physical reality would need to fulfill in order to have had a beginning and argue that, given the current state of philosophical and scientific inquiry, we cannot determine whether physical reality began to exist. -/- Friends of the KCA have sought to defend their view that physical reality began to exist in two distinct ways. As I discuss in chapter 2, the first way in which friends of the KCA have sought to defend their view that physical reality began to exist involves a family of a priori arguments meant to show that, as a matter of metaphysical necessity, the past must be finite. If the past is necessarily finite, then the past history of physical reality is necessarily finite. And if having a finite past suffices for having a beginning, then, since the past history of physical reality is necessarily finite, physical reality necessarily began to exist. I show that the arguments which have been offered thus far for the view that the past is necessarily finite do not succeed. Moreover, as I elaborate on in chapter 5, having a finite past does not suffice for having a beginning. -/- As I discuss in chapter 3, the second way in which friends of the KCA have sought to defend their view that physical reality began to exist involves a family of a posteriori arguments meant to show that we have empirical evidence that physical reality has a finite past history. For example, the big bang is sometimes claimed to have been the beginning of physical reality and, since we have excellent empirical evidence for the big bang, we have excellent empirical evidence for the beginning of physical reality. The big bang can be understood in two ways. On the one hand, the big bang can be understood as a theory about the history and development of the observable universe. Understood in that sense, then I agree that the big bang is supported by excellent empirical evidence and by a scientific consensus. On the other hand, some authors (particularly science popularizers, science journalists, and religious apologists) have wrongly interpreted big bang theory as a theory about the beginning of the whole of physical reality. As I argue, while a beginning of physical reality may be consistent with classical big bang theory, classical big bang theory does not provide good reason for thinking that physical reality began to exist. -/- In part II, I turn to discussing three necessary, but not necessarily sufficient, conditions for physical reality to have a beginning. Before discussing the three conditions, in chapter 4, I introduce three metaphysical accounts of the nature of time (A-theory, B-theory, and C-theory) as well as some formal machinery that will subsequently become useful in the dissertation. I introduce the first of the three conditions in chapter 5. According to the Modal Condition, physical reality began to exist only if, at the closest possible worlds without time, physical reality does not exist. I show that this condition helps us to make sense of various views in both theology and philosophy of physics. In chapter 6}, I introduce the second of my three conditions, the Direction Condition, according to which, roughly, physical reality began to exist only if all space-time points agree about the direction of time, so that all space-time points can agree that physical reality's putative beginning took place in their objective past. In chapter 7, I discuss the third condition, the Boundary Condition, according to which physical reality began to exist only if there is a past temporal boundary such that physical reality did not exist before the boundary. I show that there are two senses in which physical reality could be said to have had a past temporal boundary. Lastly, in chapter 8, I show that there is a relationship between my three conditions and classical big bang theory, even though the relationship is not the one usually identified in the literature. -/- In part III, I present four arguments for the view that, at the present stage of philosophical and scientific inquiry, we cannot know whether physical reality satisfies the three necessary conditions to have had a beginning and, consequently, we cannot know whether physical reality had a beginning. As I will prove in chapter 9, no set of observations that we currently have, when conjoined with General Relativity, entails that physical reality satisfies the Direction or Boundary Conditions. As I show in chapter 10, considerations in the philosophical foundations of statistical mechanics entail either that the Cosmos violates the Modal Condition or else that there is a transcendental condition on the possibility of our knowledge of the past that prevents our access to data we would need to gather to determine whether physical reality satisfies the Boundary Condition. In chapter 11, I show that there are a number of live cosmological models according to which physical reality does not satisfy the Boundary Condition. As long as we don't know whether any of those cosmological models are correct, we do not know whether physical reality satisfies the Boundary Condition. Lastly, I turn to confirmation theory and show that, at our present stage of inquiry, ampliative inferences for the conclusion that physical reality satisfies the Modal, Direction, and Boundary Conditions are not successful. (shrink)

In this paper, I aim to resolve the Frierson-Grenberg debate on the nature of Kant’s account of moral motivation that took place in the third issue of Con-textos Kantianos. In their respective interpretations, Frierson and Grenberg fail to accommodate the a priori status of moral feeling when incorporating it into Kant’s moral motivational structure. In response, I provide a novel transcendental interpretation – one that takes the a priori moral feeling both as an incentive of morality and as (...) that which conditions the possibility of morality in human agents. I argue that Kant developed the notion of moral feeling solely in order to resolve the problem of motivational skepticism concerning the moral law. Since this problem occurs as a part of Kant’s search for the supreme principle of morality, the notion of moral feeling becomes a part of both Kant’s moral motivational structure and his argument to justify the moral law. (shrink)

This concluding chapter of FREEDOM AND MORAL SENTIMENT (OUP 1995) provides a qualified defense of Hume's naturalistic approach to the problem of free will and moral responsibility. A particularly important theme is the contrast between Hume's naturalistic approach and the “rationalistic” approach associated with classical compatibilism. Whereas the rationalistic approach proceeds as an a priori, conceptual investigation into the nature and conditions of moral responsibility, the naturalistic approach is committed to an empirically oriented (i.e., psychologically informed) examination of these (...) issues – giving particular prominence to the role of moral sentiment in understanding moral life and the place of justificatory issues as they arise within it. Whereas the rationalistic approach leads us into intractable difficulties and moral skepticism, the naturalistic approach makes real progress on this subject. On a more critical note, however, I also argue that, despite its strengths, Hume's theory of moral responsibility has significant weaknesses in the areas of moral virtue, moral capacity, and moral freedom. -/- . (shrink)

Inspired by Rudolf Carnap's Der Logische Aufbau Der Welt, David J. Chalmers argues that the world can be constructed from a few basic elements. He develops a scrutability thesis saying that all truths about the world can be derived from basic truths and ideal reasoning. This thesis leads to many philosophical consequences: a broadly Fregean approach to meaning, an internalist approach to the contents of thought, and a reply to W. V. Quine's arguments against the analytic and the a (...) class='Hi'>priori. Chalmers also uses scrutability to analyze the unity of science, to defend a conceptual approach to metaphysics, and to mount a structuralist response to skepticism. Based on the 2010 John Locke lectures, Constructing the World opens up debate on central philosophical issues involving language, consciousness, knowledge, and reality. This major work by a leading philosopher will appeal to philosophers in all areas. This entry contains uncorrected proofs of front matter, chapter 1, and first excursus. (shrink)

Argues against several influential a priori arguments for individualism in the philosophy of mind that were influential in the 1980s.

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.

This chapter considers Kant's relation to Hume as Kant himself understood it when he wrote the Critique of Pure Reason and the Prolegomena. It first seeks to refine the question of Kant's relation to Hume's skepticism, and it then considers the evidence for Kant's attitude toward Hume in three works: the A Critique, Prolegomena, and B Critique. It argues that in the A Critique Kant viewed skepticism positively, as a necessary reaction to dogmatism and a spur toward critique. (...) In his initial statement of the critical philosophy Kant treated Hume as an ally in curbing dogmatism, but one who stopped short of what was really needed: a full critique of reason, to establish the boundaries of metaphysical cognition. Kant found fault with Hume's analyses of cognition and experience, and specifically his failure to see the crucial importance of synthetic a priori cognition in metaphysics. In particular, he held that Hume's empiricist account of cognition could neither explain the synthetic a priori cognition actually found in mathematics and natural science, nor provide a principled account of the limits on what can be known--and what can be thought--through the pure concepts of the understanding. According to Kant, Hume therefore failed in his attempt to determine the limits of metaphysics, whereas he was able to succeed because his transcendental philosophy provided a thorough account of cognition, its structure and limits. In the Prolegomena and the B Critique Kant distinguished his position more sharply from Hume's. He also adopted a more negative attitude toward "skeptical idealism" than before; but he attributed such skepticism to Descartes, not Hume. Prior to the B Critique Kant did not see Hume as attacking natural science or ordinary cognition. In none of the three works was Kant's main aim to "answer the skeptic." His primary aim was to firmly establish the boundary of metaphysics, by discovering the elements of human cognition and fixing its proper domain. His purported discoveries about the limits of metaphysical cognition meant that the traditional objects of metaphysical knowledge, God, the soul, and the world as it is in itself, are unknowable, hence that traditional metaphysics itself is impossible. Besides settling the possibility or impossibility of metaphysics, his findings would also prevent the illegitimate extension of principles of sensibility to God and the noumenal self, an extension that would threaten the metaphysics of morals by incorrectly denying the thinkability of noumenal freedom, and that might otherwise lead to "materialism, fatalism, atheism, and freethinking unbelief" (B xxxiv). (shrink)

Kripke’s examples of allegedly contingent a priori sentences include ‘Stick S is exactly one meter long’, where the reference of ‘meter’ is fixed by the description ‘the length of stick S’. In response to skepticism concerning apriority Kripke replaced the meter sentence with a more sophisticated variant, arguing that the modified example is more immune to such skepticism. The case for apriority is examined. A distinction is drawn between apriority and a broader notion, “qua-priority,” of a truth (...) whose epistemic justification is dependent on no experience other than that required to justify belief of the deliverances of pure semantics. It is argued that Kripke’s examples are neither a priori nor qua-priori. (shrink)

Recent third person approaches to thought experiments and conceptual analysis through the method of surveys are motivated by and motivate skepticism about the traditional first person method. I argue that such surveys give no good ground for skepticism, that they have some utility, but that they do not represent a fundamentally new way of doing philosophy, that they are liable to considerable methodological difficulties, and that they cannot be substituted for the first person method, since the a (...) class='Hi'>priori knowledge which is our object in conceptual analysis can be acquired only from the first person standpoint. (shrink)

In the later Fichte the reflection splits the world into a fivefoldness of its possible view. To get through all the a priori arranged levels from sensuality to the Doctrine of Science means to use up all the possibilities of the views of the world. I will examine whether Fichte can offer us a direct proof of completeness of the standpoints or at least show indirectly that there must be exactly five of them. Which answer would he give us (...) if we argued that history, skepticism and nonentity could complement the array? -/- Keywords Fivefoldness-worldviews-completeness-proof-history-skepticism -/- Die Reflexion spaltet nach Fichte die Welt in eine Fünffachheit ihrer möglichen Ansicht. Das Durchlaufen der a priori geordneten Stufen von der Sinnlichkeit bis zur Wissenschaftslehre stellt zugleich ein Ausschöpfen der Möglichkeiten dar, sich zur Welt zu verhalten. Ich werde prüfen, ob Fichte uns einen direkten Beweis der Vollständigkeit der Standpunkte geben oder zumindest indirekt dafür argumentieren kann, dass es genau fünf sein müssen. Was würde er uns antworten, wenn wir behaupteten, die Geschichte, der Skeptizismus und die Nullität könnten die Reihe ergänzen? -/- Schlüsselbegriffe Fünffachheit-Weltansichten-Vollständigkeit-Beweis-Geschichte-Skeptizismus. (shrink)

This paper attempts to shed light on three sets of issues that bear directly on our understanding of Locke and Kant. The first is whether Kant believes Locke merely anticipates his distinction between analytic and synthetic judgments or also believes Locke anticipates his notion of synthetic a priori cognition. The second is what should we as readers of Kant and Locke should think about Kant’s view whatever it turns out to be, and the third is the nature of Kant’s (...) justification for the comparison he draws between his philosophy and Locke’s. I argue (1) that Kant believes Locke anticipates both the analytic-synthetic distinction and Kant’s notion of synthetic a priori cognition, (2) that the best justification for Kant’s claim draws on Locke’s distinction between trifling and instructive knowledge, (3) that the arguments against this claim developed by Carson, Allison, and Newman fail to undermine it, and (4) that Kant’s own justification for his claim is quite different from what many commentators have thought it was (or should have been). (shrink)

Sober and Elgin defend the claim that there are a priori causal laws in biology. Lange and Rosenberg take issue with this on Humean grounds, among others. I will argue that Sober and Elgin don’t go far enough – there are a priori causal laws in many sciences. Furthermore, I will argue that this thesis is compatible with a Humean metaphysics and an empiricist epistemology.

The justificatory force of empirical reasoning always depends upon the existence of some synthetic, a priori justification. The reasoner must begin with justified, substantive constraints on both the prior probability of the conclusion and certain conditional probabilities; otherwise, all possible degrees of belief in the conclusion are left open given the premises. Such constraints cannot in general be empirically justified, on pain of infinite regress. Nor does subjective Bayesianism offer a way out for the empiricist. Despite often-cited convergence theorems, (...) subjective Bayesians cannot hold that any empirical hypothesis is ever objectively justified in the relevant sense. Rationalism is thus the only alternative to an implausible skepticism. (shrink)

Modal intuitions are the primary source of modal knowledge but also of modal error. According to the theory of modal error in this paper, modal intuitions retain their evidential force in spite of their fallibility, and erroneous modal intuitions are in principle identifiable and eliminable by subjecting our intuitions to a priori dialectic. After an inventory of standard sources of modal error, two further sources are examined in detail. The first source - namely, the failure to distinguish between metaphysical (...) possibility and various kinds of epistemic possibility - turns out to be comparatively easy to untangle and poses little threat to intuition-driven philosophical investigation. The second source is the local misunderstanding of one's concepts . This pathology may be understood on analogy with a patient who is given a clean bill of health at his annual check-up, despite his having a cold at the time of the check-up: although the patient's health is locally disrupted, his overall health is sufficiently good to enable him to overcome the cold without external intervention. Even when our understanding of certain pivotal concepts has lapsed locally, our larger body of intuitions is sufficiently reliable to allow us, without intervention, to ferret out the modal errors resulting from this lapse of understanding by means of dialectic and/or a process of a priori reflection. This source of modal error, and our capacity to overcome it, has wide-ranging implications for philosophical method - including, in particular, its promise for disarming skepticism about the classical method of intuition-driven investigation itself. Indeed, it is shown that skeptical accounts of modal error are ultimately self-defeating. (shrink)

This article discusses the role of a priori and a posteriori knowledge and methods in metaphysics and metametaphysics. Issues discussed include the viability of the distinction, the continuity of a priori and a posteriori methods, connections to modal epistemology, and the role of the distinction for science and naturalistic metaphysics.

In this paper I will offer a novel understanding of a priori knowledge. My claim is that the sharp distinction that is usually made between a priori and a posteriori knowledge is groundless. It will be argued that a plausible understanding of a priori and a posteriori knowledge has to acknowledge that they are in a constant bootstrapping relationship. It is also crucial that we distinguish between a priori propositions that hold in the actual world and (...) merely possible, non-actual a priori propositions, as we will see when considering cases like Euclidean geometry. Furthermore, contrary to what Kripke seems to suggest, a priori knowledge is intimately connected with metaphysical modality, indeed, grounded in it. The task of a priori reasoning, according to this account, is to delimit the space of metaphysically possible worlds in order for us to be able to determine what is actual. (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)

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 (...) class='Hi'>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)

In this paper, I sketch an argument for the view that we cannot know (or have good reasons to believe) that God exists. Some call this view “strong agnosticism” but I prefer the term “skeptheism” in order to clearly distinguish between two distinct epistemic attitudes with respect to the existence of God, namely, agnosticism and skepticism. For the skeptheist, we cannot know (or have good reasons to believe) that God exists, since there can be neither conceptual (a priori) (...) nor empirical (a posteriori) evidence for the existence of God. (shrink)

(2014). A Priori Conditionals and the Conceivability of Zombies. Philosophical Papers: Vol. 43, No. 2, pp. 227-253.

Inequalities of social goods between gender, racial, or other groups call out for explanation. Such inequalities might be explained by socialization and discrimination. But historically some have attributed these inequalities to biological differences between social groups. Such explanations are highly controversial: on the one hand, they have a very troubling racist and sexist history, but on the other hand, they are empirical claims, and so it seems inappropriate to rule them out a priori. I propose that the appropriate epistemic (...) attitude toward biological explanations of social inequalities is a general but defeasible skepticism. I then turn to the appropriate moral attitude, arguing that when such explanations are inadequately supported, they are offensive. (shrink)

This paper develops the situational model of primate beliefs from the Prior-Lurz line of thought. There is a strong skepticism concerning primate beliefs in the analytic tradition which holds that beliefs have to be propositional and non-human animals do not have them. The response offered in this paper is twofold. First, two arguments against the propositional model as applied to other animals are put forward: an a priori argument from referential opacity and an empirical argument from varieties of (...) working memory. Second, the Prior-Lurz situational model based on state of affairs as opposed to propositions is introduced and defended with two significant modifications. With this model of primate beliefs we can make progress in understanding how other primates can have certain mindreading capacity. (shrink)

In his recent book Constructing the World, David Chalmers defends A Priori Scrutability, the thesis that there is a compact class of truths such that for any truth p, a Laplacian intellect could know a priori that if the truths in that class hold, then p. In this paper, I develop an objection to Chalmers’ thesis that focuses on his treatment of a so-called that’s-all truth. My objection draws on Theodore Sider’s discussion of border-sensitive properties, and also on (...) the causal phenomenon of double prevention. (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)

To reject skepticism and lay the foundation for the certainty of knowledge, Kant raised the question of how synthetic a priori proposition is possible. In his solution, the new content of knowledge comes from the syntheses of experience a posteriori, and the universal necessity of knowledge is guaranteed by it’s a priority. Under the influence of Kant, the concept of a priori and necessity has long been regarded as coextensive. But Saul Kripke believes that this will confuse (...) different philosophical fields: a priori is an epistemological concept, which involves the way or means of acquiring knowledge, and necessity is a metaphysical concept, which involves the possible ways or states of the world. The key point is that, on Kripke, there is no necessary connection between these two fields. He raised some famous examples of the necessary a posteriori. More remarkably, in his explanation of necessary a posteriori, although he did not clearly propose the distinction between epistemic possibility and metaphysical possibility, he had laid the foundation for this distinction. Furthermore, on Manuel Garcia-Carpintero and Josep Macia, when Kripke talks about necessary a posteriori by appealing to two relevant expressions, what he proposed can be taken as kind of ‘blueprint for 2-D accounts’. (Manuel Garcia-Carpintero and Josep Macia, 2006, p.2) There are different forms of two-dimensionalism in semantics. I will focus on David Chalmers’s epistemic version and Scott Soames’ criticism. With the framework of possible world semantics established by Kripke and others, David Chalmers’ epistemic two-dimensionalism deals with the relationship between epistemic and metaphysical modalities from a quite different perspective, and then gives an elegant definition to necessary a posteriori and other modal concepts. Scott Soames criticized two-dimensionalism based on Kripke's modal realism and essentialism, and developed Kripke's account of necessary a posteriori. But according to Chalmers, Soames also uses a two-dimensional system himself to analyze cases of the necessary a posteriori. In the first two part of this paper I will briefly introduce the epistemic two-dimensionalism and specify the similarities between Kripke-Soames and Chalmers when they interpret necessary a posteriori. In the third part I turn to their difference by the analysis of relationship between epistemic possibility and metaphysical possibility which is the key issue for illuminating necessary a posteriori. (shrink)

On rationalist infallibilism, a wide range of both (i) analytic and (ii) synthetic a priori propositions can be infallibly justified, i.e., justified in a way that is truth-entailing. In this paper, I examine the second thesis of rationalist infallibilism, what might be called ‘synthetic a priori infallibilism’. Exploring the seemingly only potentially plausible species of synthetic a priori infallibility, I reject the infallible justification of so-called self-justifying propositions.

The topic of a priori knowledge is approached through the theory of evidence. A shortcoming in traditional formulations of moderate rationalism and moderate empiricism is that they fail to explain why rational intuition and phenomenal experience count as basic sources of evidence. This explanatory gap is filled by modal reliabilism -- the theory that there is a qualified modal tie between basic sources of evidence and the truth. This tie to the truth is then explained by the theory of (...) concept possession: this tie is a consequence of what, by definition, it is to possess (i.e., to understand) one’s concepts. A corollary of the overall account is that the a priori disciplines (logic, mathematics, philosophy) can be largely autonomous from the empirical sciences. (shrink)

The primary aim of this chapter is to evaluate whether considerations about a priori domains and abstract objects favor atheism over theism.

The history of western philosophy is split to its core by a long-standing, fundamental dispute. On the one hand there are the so-called empiricists, like Locke, Berkeley, Hume, Mill, Russell, the logical positivists, A. J. Ayer, Karl Popper and most scientists, who hold empirical considerations alone can be appealed to in justifying, or providing a rationale for, claims to factual knowledge, there being no such thing as a priori knowledge – items of factual knowledge that are accepted on grounds (...) other than the empirical. And on the other hand there are the so-called rationalists, like Descartes, Spinoza, Leibniz, Bradley, McTaggart, who hold that a priori knowledge does exist, and even plays a crucial role in science. This long-standing dispute is resolved by the line of thought developed in this essay. The empiricists were right to deny the existence of a priori knowledge where this means factual knowledge of apodictic certainty justified independently of any appeal to experience. They were wrong, however, to deny the existence of a priori knowledge where this means conjectural items of factual knowledge whose acceptance is justified independently of any appeal to experience. Science requires there to be a priori knowledge in this latter sense, and two items of such knowledge will be exhibited. In addition to resolving this empiricist/rationalist dispute, the essay also develops a new conception of science – aim-oriented empiricism – and solves the long-standing problem of what it means to say of a theory that it is unified or explanatory. Furthermore, aim-oriented empiricism does not just change our conception of science; it requires that science itself needs to change. Science needs to become much more like the 17th century conception of natural philosophy, intermingling consideration of testable theories with consideration of untestable metaphysical, epistemological and methodological ideas. The whole relationship between science and the philosophy of science is transformed. The philosophy of science, construed as the exploration and critical assessment of rival ideas about what the aims and methods of science ought to be, ceases to be a meta-discipline, and becomes an integral part of science – or natural philosophy – itself. (shrink)

The idea that the epistemology of modality is in some sense a priori is a popular one, but it has turned out to be difficult to precisify in a way that does not expose it to decisive counterexamples. The most common precisifications follow Kripke’s suggestion that cases of necessary a posteriori truth that can be known a priori to be necessary if true ‘may give a clue to a general characterization of a posteriori knowledge of necessary truths’. The (...) idea is that whether it is contingent whether p can be known a priori for at least some broad range of sentences ‘p’. Recently, Al Casullo and Jens Kipper have discussed restrictions of such principles to atomic sentences. We show that decisive counterexamples even to such dramatically restricted Kripke-style principles can be constructed using minimal logical resources. We then consider further restrictions, and show that the counterexamples to the original principles can be turned into counterexamples to the further restricted principles. We conclude that, if there are any true restrictions of Kripke-style principles, then they are so weak as to be of little epistemological interest. (shrink)

This paper examines popular‘conventionalist’explanations of why philosophers need not back up their claims about how‘we’use our words with empirical studies of actual usage. It argues that such explanations are incompatible with a number of currently popular and plausible assumptions about language's ‘social’character. Alternate explanations of the philosopher's purported entitlement to make a priori claims about‘our’usage are then suggested. While these alternate explanations would, unlike the conventionalist ones, be compatible with the more social picture of language, they are each shown (...) to face serious problems of their own. (shrink)

This is the second in a two part series of articles that attempt to clarify the nature and enduring relevance of Kant's concept of a priori knowledge. (For Part I, see below.) In this article I focus mainly on Saul Kripke's critique of Kant, in Naming and Necessity. I argue that Kripke draws attention to a genuine defect in Kant's epistemological framework, but that he used definitions of certain key terms that were quite different from Kant's definitions. When Kripke's (...) definitions are replaced by Kant's definitions, Kripke's account of the status of naming turns out to be a defense of analytic aposteriority as a significant classification of knowledge that Kant neglected. I also introduce here a new way of understanding such epistemological labels, as defining the perspective adopted by the knowing subject in a given situation, rather than an objective characteristic of certain propositions as such. (shrink)

In this paper I argue for a priori conjectural scientific knowledge about the world. Physics persistently only accepts unified theories, even though endlessly many empirically more successful disunified rivals are always available. This persistent preference for unified theories, against empirical considerations, means that physics makes a substantial, persistent metaphysical assumption, to the effect that the universe has a (more or less) unified dynamic structure. In order to clarify what this assumption amounts to, I solve the problem of what it (...) means to say of a theory that it is unified. There are, I argue, eight different kinds of unity important in theoretical physics, all varieties of one basic idea. This provides us with a precise way of partially ordering physical theories with respect to their degree of unity. It also leads to a hierarchical view of physics, according to which physics makes a number of increasingly insubstantial metaphysical assumptions concerning the comprehensibility and knowability of the universe. Two of these are identified as constituting a priori conjectures. I conclude by arguing that the view developed in the paper resolves the traditional clash between empiricism and rationalism in the philosophy of science, and has important implications for science, and for academic inquiry more generally. (shrink)

O objectivo deste artigo consiste em introduzir a noção de conhecimento a priori e os problemas que a envolvem. Começa-se por caracterizar o conhecimento a priori e aquilo que o distingue do conhecimento a posteriori para de seguida avaliar-se as dificuldades que uma compreensão adequada da noção de independência da experiência enfrenta. A noção de a priori é distinguida da de necessidade, à qual, tradicionalmente, tem sido associada. Por fim, o problema do a priori é formulado (...) e as principais teorias que a ele respondem brevemente discutidas. (shrink)

The present paper deals with the ontological status of numbers and considers Frege ́s proposal in Grundlagen upon the background of the Post-Kantian semantic turn in analytical philosophy. Through a more systematic study of his philosophical premises, it comes to unearth a first level paradox that would unset earlier still than it was exposed by Russell. It then studies an alternative path, that departin1g from Frege’s initial premises, drives to a conception of numbers as synthetic a priori in a (...) more Kantian sense. On this basis, it tentatively explores a possible derivation of basic logical rules on their behalf, suggesting a more rudimentary basis to inferential thinking, which supports reconsidering the difference between logical thinking and AI. Finally, it reflects upon the contributions of this approach to the problem of the a priori. (shrink)

This paper argues there are crucial points in Nietzsche’s texts where he offers a priori epistemic justification for views he believes are correct. My reading contrasts with the dominant view that Nietzsche’s philosophical naturalism is incompatible with a priori justification. My aim is to develop Nietzsche’s brand of a priori justification, show that he employs this account of justification in the texts, and suggest how it might be compatible with naturalism.

The epistemic status of Natural Selection has intrigued to biologists and philosophers since the very beginning of the theory to our present times. One prominent contemporary example is Elliott Sober, who claims that Natural Selection, and some other theories in biology, and maybe in economics, are peculiar in including explanatory models/conditionals that are a priori in a sense in which explanatory models/conditionals in Classical Mechanics and most other standard theories are not. In this paper, by analyzing what we take (...) to be the four possible interpretations of Sober’s claim, we argue that, terminological preferences aside, the possible senses in which explanatory models in Natural Selection can qualify, or include elements that can qualify, as a priori, also apply to Classical Mechanics and other standard, highly unified theories. (shrink)