The distinction between a priori knowledge and a posteriori knowledge has come under attack in the recent literature by Philip Kitcher, John Hawthorne, C. S. Jenkins, and Timothy Williamson. Evaluating the attacks requires answering two questions. First, have they hit their target? Second, are they compelling? My goal is to argue that the attacks fail because they miss their target. Since the attacks are directed at a particular concept or distinction, they must accurately locate the target concept or distinction. (...) Accurately locating the target concept or distinction requires correctly articulating that concept or distinction. The attacks miss their target because they fail to correctly articulate the target concept or distinction. I go on to present a different challenge to the a priori-a posteriori distinction. This challenge is not directed at the coherence or significance of the distinction. Its target is the traditional view that all knowledge (or justified belief) is either a priori or a posteriori. (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 challenges the Kripkean interpretation of a posteriori necessities. It will be demonstrated, by an analysis of classic examples, that the modal content of supposed a posteriori necessities is more complicated than the Kripkean line suggests. We will see that further research is needed concerning the a priori principles underlying all a posteriori necessities. In the course of this analysis it will emerge that the modal content of a posteriori necessities can be best described in (...) terms of a Finean conception of modality – by giving essences priority over modality. The upshot of this is that we might be able to establish the necessity of certain supposed a posteriori necessities by a priori means. (shrink)

This paper is an examination of the contingent a priori and the necessary a posteriori. In particular, it considers -- and assesses -- the criticisms that Nathan Salmon makes of the views of Saul Kripke.

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)

Kripke’s main argument against descriptivism is rooted in a category error that confuses statements about the world with statements about models of the world. It is only because of the ambiguity introduced by the fact that a single sentence can frame two different propositions, one necessary and the other a posteriori, that one reaches the mistaken conclusion that there can be necessary a posteriori truths. This ambiguity from language was carried over into modal logic by Kripke. However, we (...) must consider the two different propositions (1) and (2) separately. Doing so reveals that a given proposition is either necessary and a priori or contingent and a posteriori. It cannot be both. (shrink)

Introspection presents our phenomenal states in a manner otherwise than physical. This observation is often thought to amount to an argument against physicalism: if introspection presents phenomenal states as they essentially are, then phenomenal states cannot be physical states, for we are not introspectively aware of phenomenal states as physical states. In this article, I examine whether this argument threatens a posteriori physicalism. I argue that as along as proponents of a posteriori physicalism maintain that phenomenal concepts present (...) the nature of their referents in a partial and incomplete manner, a posteriori physicalism is safe. (shrink)

I critically assess Stephen Yablo’s claim that cassinis are ovals is an a posteriori conceptual necessity. One does not know it simply by mastering the relevant concepts but by substantial empirical scrutiny. Yablo represents narrow content by would have turned out -conditionals. An epistemic reading of such conditionals does not bear Yablo’s claim. Two metaphysically laden readings are considered. In one reading, Yablo’s conditionals test under what circumstances concepts remain the same while their extensions diverge. As an alternative, I (...) develop a more literal metaphysical interpretation: Yablo’s conditionals draw on scenarios which are qualitatively identical to some original situation. None of these interpretations sustains Yablo’s core thesis. (shrink)

The traditional way of drawing the a priori/a posteriori distinction, bequeathed to us by Kant, leads to overestimating the role that experience plays in justifying ourbeliefs. There is an irony in this: though Kant was in the rationalist camp, his way of drawing the distinction gives an unfair advantage to radical empiricism. I offer an alternative way of drawing the distinction, one that does not bias the rationalist/empiricist debate.

Orthodox neural materialists think mental states are neural events or orthodox material properties of neutral events. Orthodox material properties are defining properties of the “physical”. A “defining property” of the physical is a type of property that provides a necessary condition for something’s being correctly termed “physical”. In this paper I give an argument against orthodox neural materialism. If successful, the argument would show at least some properties of some mental states are not orthodox material properties of neural events. Opposing (...) philosophical orthodoxy, I show there are no posteriori identities -- identities that cannot be known of a priori. (shrink)

The article analyzes the a posteriori argumentation for the existence of God present in saint Anselm’s Monologion. It defends that the arguments in chapters I-IV are parts of a single argumentative way comparable with the fourth way of Thomas Aquinas. The only starting point for the argumentation is the evidence of the degrees of transcendental perfection (goodness and greatness) found in things. According to this single point of departure, the argument also has a single formulation of the principle of (...) causality given in chapter I. By this principle, Anselm infers the existence of a single first principle (that which is through itself) from its effects (that which is through another). Contrary to what is usually held, it is shown that chapters III and IV do not contain arguments properly meant to demonstrate God’s existence. Chapter III’s specific goal is to demonstrate the impossibility that that which is through itself may be something multiple, while chapter IV aims to demonstrate the impossibility that the supreme nature through whom all things exist may be overcome or equaled in dignity by another. Both arguments depend of the principle of causality formulated in chapter I to be conclusive. (shrink)

This paper argues for and explores the implications of the following epistemological principle for knowability a priori (with 'Ka' abbreviating 'it is knowable a priori that'). -/- (AK) For all ϕ, ψ such that ϕ semantically presupposes ψ: if Ka(ϕ), Ka(ψ). -/- Well-known arguments for the contingent a priori and a priori knowledge of logical truth founder when the semantic presuppositions of the putative items of knowledge are made explicit. Likewise, certain kinds of analytic truth turn out to carry semantic (...) presuppositions that make them ineligible as items of a priori knowledge. -/- On a happier note, I argue that (AK) offers an appealing, theory-neutral explanation of the a posteriori character of certain necessary identities, as well as an interesting rationalization for a commonplace linguistic maneuver in philosophical work on the a priori. (shrink)

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)

Epistemic two-dimensional semantics, advocated by Chalmers and Jackson, among others, aims to restore the link between necessity and a priority seemingly broken by Kripke, by showing how armchair access to semantic intensions provides a basis for knowledge of necessary a posteriori truths. The most compelling objections to E2D are that, for one or other reason, the requisite intensions are not accessible from the armchair. As we substantiate here, existing versions of E2D are indeed subject to such access-based objections. But, (...) we moreover argue, the difficulty lies not with E2D but with the typically presupposed conceiving-based epistemology of intensions. Freed from that epistemology, and given the right alternative—one where inference to the best explanation provides the operative guide to intensions—E2D can meet access-based objections, and fulfill its promise of restoring the desirable link between necessity and a priority. This result serves as a central application of Biggs and Wilson, according to which abduction is an a priori mode of inference. (shrink)

I objected that the defeasibility theory of knowledge prohibits you from knowing that you know that p if your knowledge that p is a posteriori. Rodrigo Borges claims that Peter Klein has already satisfactorily answered a version of my objection. He attempts to defend Klein’s reply and argues that my objection fails because a principle on which it is based is false.I will show that my objection is not a version of the old one that Klein attempts (unsuccessfully) to (...) address, that Borges’ defence of Klein’s reply fails and that his argument against my new objection leaves it untouched. (shrink)

A review of Andrew Melnyk, A Physicalist Manifesto: Thoroughly Modern Materialism (Cambridge University Press, 2003).

Anti-exceptionalism about logic is the doctrine that logic does not require its own epistemology, for its methods are continuous with those of science. Although most recently urged by Williamson, the idea goes back at least to Lakatos, who wanted to adapt Popper's falsicationism and extend it not only to mathematics but to logic as well. But one needs to be careful here to distinguish the empirical from the a posteriori. Lakatos coined the term 'quasi-empirical' `for the counterinstances to putative (...) mathematical and logical theses. Mathematics and logic may both be a posteriori, but it does not follow that they are empirical. Indeed, as Williamson has demonstrated, what counts as empirical knowledge, and the role of experience in acquiring knowledge, are both unclear. Moreover, knowledge, even of necessary truths, is fallible. Nonetheless, logical consequence holds in virtue of the meaning of the logical terms, just as consequence in general holds in virtue of the meanings of the concepts involved; and so logic is both analytic and necessary. In this respect, it is exceptional. But its methodologyand its epistemology are the same as those of mathematics and science in being fallibilist, and counterexamples to seemingly analytic truths are as likely as those in any scientic endeavour. What is needed is a new account of the evidential basis of knowledge, one which is, perhaps surprisingly, found in Aristotle. (shrink)

The epistemology of essence is a topic that has received relatively little attention, although there are signs that this is changing. The lack of literature engaging directly with the topic is probably partly due to the mystery surrounding the notion of essence itself, and partly due to the sheer difficulty of developing a plausible epistemology. The need for such an account is clear especially for those, like E.J. Lowe, who are committed to a broadly Aristotelian conception of essence, whereby essence (...) plays an important theoretical role. In this chapter, our epistemic access to essence is examined in terms of the a posteriori vs. a priori distinction. The two main accounts to be contrasted are those of David S. Oderberg and E.J. Lowe. (shrink)

One type of deflationism about metaphysical modality suggests that it can be analysed strictly in terms of linguistic or conceptual content and that there is nothing particularly metaphysical about modality. Scott Soames is explicitly opposed to this trend. However, a detailed study of Soames’s own account of modality reveals that it has striking similarities with the deflationary account. In this paper I will compare Soames’s account of a posteriori necessities concerning natural kinds with the deflationary one, specifically Alan Sidelle’s (...) account, and suggest that Soames’s account is vulnerable to the deflationist’s critique. Furthermore, I conjecture that both the deflationary account and Soames’s account fail to fully explicate the metaphysical content of a posteriori necessities. Although I will focus on Soames, my argument may have more general implications towards the prospects of providing a meaning-based account of metaphysical modality. (shrink)

Modal rationalists uphold a strong constitutive relationship between a priori cognition and modal cognition. Since both a priori cognition and modal cognition have been taken to be characteristic of philosophical insights, I will critically assess an ambitious modal rationalism and an associated ambitious methodological rationalism. I begin by examining Kripkean cases of the necessary a posteriori in order to characterize the ambitious modal rationalism that will be the focus of my criticism. I then argue that there is a principled (...) association between this view in the epistemology of modality and an ambitious methodological rationalist picture of the nature of philosophical insights. On the basis of this discussion, I criticize ambitious modal rationalism and argue that the critique indicates some principled limits of generating philosophical insights by a priori modal cognition. Hence, my central diagnosis is that ambitious methodological rationalists are overly ambitious in the role that they assign a priori modal cognition in philosophical methodology. -/-. (shrink)

By the lights of a central logical positivist thesis in modal epistemology, for every necessary truth that we know, we know it a priori and for every contingent truth that we know, we know it a posteriori. Kripke attacks on both flanks, arguing that we know necessary a posteriori truths and that we probably know contingent a priori truths. In a reflection of Kripke's confidence in his own arguments, the first of these Kripkean claims is far more widely (...) accepted than the second. Contrary to received opinion, the paper argues, the considerations Kripke adduces concerning truths purported to be necessary a posteriori do not disprove the logical positivist thesis that necessary truth and a priori truth are co-extensive. (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)

Recent work on Natural Kind Essentialism has taken a deflationary turn. The assumptions about the grounds of essentialist truths concerning natural kinds familiar from the Kripke-Putnam framework are now considered questionable. The source of the problem, however, has not been sufficiently explicated. The paper focuses on the Twin Earth scenario, and it will be demonstrated that the essentialist principle at its core (which I call IDENT)—that necessarily, a sample of a chemical substance, A, is of the same kind as another (...) sample, B, if and only if A and B have the same microstructure—must be re-evaluated. The Twin Earth scenario also assumes the falsity of another essentialist principle (which I call INST): necessarily, there is a 1:1 correlation between (all of ) the chemical properties of a chemical substance and the microstructure of that substance. This assumption will be questioned, and it will be argued that, in fact, the best strategy for defending IDENT is to establish INST. The prospects for Natural Kind Essentialism and microstructural essentialism regarding chemical substances will be assessed with reference to recent work in the philosophy of chemistry. Finally, a weakened form of INST will be presented. (shrink)

The received view in the history of the philosophy of psychology is that the logical positivists—Carnap and Hempel in particular—endorsed the position commonly known as “logical” or “analytical” behaviourism, according to which the relations between psychological statements and the physical-behavioural statements intended to give their meaning are analytic and knowable a priori. This chapter argues that this is sheer legend: most, if not all, such relations were viewed by the logical positivists as synthetic and knowable only a posteriori. It (...) then traces the origins of the legend to the logical positivists’ idiosyncratic extensional or at best weakly intensional use of what are now considered crucially strongly intensional semantic notions, such as “translation,” “meaning” and their cognates, focussing on a particular instance of this latter phenomenon, arguing that a conflation of explicit definition and analyticity may be the chief source of the legend. (shrink)

It is widely accepted that physicalism faces its most serious challenge when it comes to making room for the phenomenal character of psychological experience, its so-called what-it-is-like aspect. The challenge has surfaced repeatedly over the past two decades in a variety of forms. In a particularly striking one, Frank Jackson considers a situation in which Mary, a brilliant scientist who knows all the physical facts there are to know about psychological experience, has spent the whole of her life in a (...) black and white room. He asks, What will happen when Mary is released from her black and white room or is given a colour television monitor? Will she learn anything or not? It seems just obvious that she will learn something about the world and our visual experience of it. But then it is inescapable that her previous knowledge was incomplete. But she had all the physical information. (Jackson 1986: 130). (shrink)

Descartes was both metaphysician and natural philosopher. He used his metaphysics to ground portions of his physics. However, as should be a commonplace but is not, he did not think he could spin all of his physics out of his metaphysics a priori, and in fact he both emphasized the need for appeals to experience in his methodological remarks on philosophizing about nature and constantly appealed to experience in describing his own philosophy of nature. During the 1630s, he offered empirical (...) support for the basic principles of his natural philosophy, while also promising to provide a metaphysical justification. He offered the metaphysical justification in the Meditations and Principles. and claimed absolute certainty for it. At the same time, he recognized that the particular postulated mechanisms of his natural philosophy did not reach that standard of certainty. These mechanisms were supported by empirical testing or confirming of causes through observed effects. (shrink)

A Crítica de Hume ao Argumento do Desígnio José Oscar de Almeida Marques Dep. de Filosofia – UNICAMP -/- RESUMO: É comum considerar que o chamado “argumento do desígnio” (o argumento a posteriori para provar a existência de Deus a partir da ordem e funcionalidade do mundo) teria sido refutado ou seriamente abalado por Hume. Mas a natureza e o alcance dessa alegada refutação são problemáticos, pois Hume muitas vezes expressou suas críticas através de seus personagens e evitou assumi-las (...) diretamente enquanto autor. Em vez de supor que Hume procedeu dessa forma apenas para disfarçar suas verdadeiras convicções e evitar um conflito com as autoridades eclesiásticas, proponho que sua posição nesse assunto não é tão categórica como às vezes se supõe, e que os famosos argumentos de Filo nos Diálogos mostram apenas que é possível que a ordem e funcionalidade do mundo tenham surgido sem a intervenção de um desígnio consciente, mas não podem por si sós dar a essa hipótese o mínimo grau de plausibilidade necessário para torná-la digna de uma séria consideração. De fato, antes da revolução explicativa operada por Darwin um século depois, ninguém estava realmente em condições de vislumbrar uma alternativa plausível à atuação de algum tipo de inteligência na geração da ordem e funcionalidade do mundo. ------------ Some Remarks on Hume’s Critique of the Argument from Design José Oscar of Almeida Marques Dep. of Philosophy - UNICAMP -/- ABSTRACT: The so-called “argument from design” (the a posteriori argument to prove the existence of God from the order and functionality of the world) is commonly considered to have been refuted or seriously impaired by Hume. But the nature and scope of this alleged refutation is problematic because Hume often expressed his critics through other characters’ mouth and avoided to assume them directly as author. Contrarily to the supposition that Hume proceeded in this way only to disguise his true convictions and to avoid a confrontation with the ecclesiastical authorities, I propose that his stance on the matter is not, in fact, as clear-cut as it is sometimes supposed, and that Philo’s famous arguments in the Dialogues show only that it is possible for the order and functionality of the world to have arisen without the intervention of an intelligent design, but cannot by themselves lend to this hypothesis the least degree of plausibility needed to make it worthy of serious consideration. In fact, before the explanatory revolution inaugurated by Darwin a century later, nobody was in position to envisage a plausible alternative to the operation of some sort or other of intelligence in the generation of the order and functionality of the world. (shrink)

John N. Williams argued that Peter Klein's defeasibility theory of knowledge excludes the possibility of one knowing that one has a posteriori knowledge. He does that by way of adding a new twist to an objection Klein himself answered more than forty years ago. In this paper I argue that Williams' objection misses its target because of this new twist.

According to rationalists about moral knowledge, some moral truths are knowable a priori. Rationalists often defend their position by claiming that some moral propositions are self-evidently true. Copp 2007 has recently challenged this rationalist strategy. Copp argues that even if some moral propositions are self-evident, this is not enough to secure rationalism about moral knowledge, since it turns out that such self-evident propositions are only knowable a posteriori. This paper considers the merits of Copp’s challenge. After clarifying the rationalists’ (...) appeal to self-evidence, I show why this rationalist strategy survives Copp’s challenges to it. (shrink)

This article attempts to make sense of property contingentism, the view that the metaphysical nature of properties is contingent. That is, it is contingent whether properties are universals or tropes or some other kind of entity. The article argues that even if one thinks that necessities are exhausted by conceptual truths and a posteriori necessities, the sort of methodology that can lead one to endorse contingentism in various domains in metaphysics does not give us good grounds to suppose that (...) the nature of properties is contingent. (shrink)

This paper challenges the standard a priori/a posteriori distinction by looking at statements in which comprehension requires more that merely passive awareness of objects and their properties. A proposal is made to add to the traditional categories of knowledge, the “a positio,” characterized by active, intentional, and collective involvement of language users in the existence and nature of objects of reference needed for the truth of statements about various kinds of artifacts, broadly construed. The conditions of understanding statements about (...) institutions, institutional activity and standards of measurement are considered in some detail. (shrink)

In this paper, it is argued that there can be necessary and non-natural desires. After a discussion about what seems wrong with such desires, Epicurus’ classification of desires is treated similarly to Kripke’s treatment of the Kantian table of judgments. A sample of three cases is suggested to make this point.

According to the identity theory of the mind every mental state is equal to a physical brain state and can be reduced to it. The risk of this kind of reduction is that we also reduce away consciousness and have to deny the existence of the phenomenological qualitative character of our mind. Kripke argues that identity theory cannot be true, but what I will try to show in this paper is that we can hold a form of identity theory and (...) still believe in the subjective experience of our mind. For this I will use a paper by Nagel in which he suggest the existence of a concept to which both mental and physical properties can be reduced. (shrink)

The purpose of this book is to address the controversial issues of whether we have a fixed set of ontological categories and if they have some epistemic value at all. Which are our ontological categories? What determines them? Do they play a role in cognition? If so, which? What do they force to presuppose regarding our world-view? If they constitute a limit to possible knowledge, up to what point is science possible? Does their study make of philosophy a science? Departing (...) from the novelty –but no exclusively- of considering distinctions to be the subject matter of thought and language -that is, of reference and meaning- the author arrives at a radical novel conception of the ontological categories. The observations and arguments presented in it constitute a strong case against established and well-rooted tenets, if not paradigms, of contemporary philosophy, beyond ontology and epistemology. The entailing conclusions, open the door to a revival of the discipline and the importance of its studies, as the science of the constitutive elements of knowledge of a non-empirical nature. (shrink)

The sustainability challenge is to match cultural and natural change. Instead of a political or institutional approach, this implies a cultural revolution in the domain of individual ethics. I defend this ethical priority in sustainability through an a posteriori argument concerning institutional failure and through a conceptual analysis of sustainability as self-reliance and its consequences. Sustainability is not a challenge for our institutions directly. It is a challenge for our lifestyle, our personal lifestyle and our social lifestyle (institutional, economical (...) and political). Our lifestyles are not 'sustainable' in the full sense of the word. They will not last, and they do not meet the requirements of human dignity (ethical and ecological dignity). (shrink)

This essay is about the way Kant sees the world rather than about his moral philosophy and his theories of justice. It concentrates on perception of the physical world, and how far this can take us in understanding the world of the mind and how we think and make decisions about our lives. It proposes that Kant can be seen as the founder not just of theories of the problem of knowledge, but also of such modern ideas as existentialism.

Kripke, argued like this: it seems possible that E; the appearance can't be explained away as really pertaining to a "presentation" of E; so, pending a different explanation, it is possible that E. Textbook Kripkeans see in the contrast between E and its presentation intimations of a quite general distinction between two sorts of meaning. E's secondary or a posteriori meaning is the set of all worlds w which E, as employed here, truly describes. Its primary or a priori (...) meaning is the set of all w such that if w is actual, then E is true. "Conceivability error" occurs when a primary possibility is mistaken for a secondary one. Textbook Kripkeanism is rejected on the grounds that it makes meaning too modal and modality too much a matter of meaning. (shrink)

In this chapter, I defend the program of conceptual analysis, broadly construed, and the method of thought experiments in epistemology, as a first-person enterprise, that is, as one which draws on the investigator's own competence in the relevant concepts. I do not suggest that epistemology is limited to conceptual analysis, that it does not have important a posteriori elements, that it should not draw on empirical work wherever relevant (and non-question begging), or that it is not a communal enterprise. (...) Although discussion in the space available will necessarily be brief, and many points must be elided altogether, I aim to sketch salient features of the landscape, clarify issues, set aside some confusions, and outline responses to some recent challenges. In §2, I sketch a traditional account of concepts and conceptual truths. In §3, I review a broad conception of analysis as encompassing not just reduction but also articulation of conceptual connections. In §4, I address the charge that in studying epistemic concepts we turn away from our proper target of study, the actual phenomena of knowledge, justification, and so on. In §5, I give a brief overview of the method of thought experiments. In §6, I address objections to thought experiments that have their source in "experimental philosophy." In §7, I address the charge that pursuing conceptual analysis in epistemology is misplaced because 'knowledge', 'justification', 'evidence' and so on, are natural kind terms, and hence that we must engage in empirical research to discover the real essences of the kinds they pick out (if any). (shrink)

In his 1993 article ‘The Coming Technological Singularity: How to survive in the posthuman era’ the computer scientist Virnor Vinge speculated that developments in artificial intelligence might reach a point where improvements in machine intelligence result in smart AI’s producing ever-smarter AI’s. According to Vinge the ‘singularity’, as he called this threshold of recursive self-improvement, would be a ‘transcendental event’ transforming life on Earth in ways that unaugmented humans are not equipped to envisage. In this paper I argue Vinge’s idea (...) of a technologically led intelligence explosion is philosophically important because it requires us to consider the prospect of a posthuman condition succeeding the human one. What is the ‘humanity’ to which the posthuman is ‘post’? Does the possibility of a posthumanity presuppose that there is a ‘human essence’, or is there some other way of conceiving the human-posthuman difference? I argue that the difference should be conceived as a historically emergent disconnection between individuals, not in terms of the presence or lack of essential properties. I also suggest that these individuals should not be conceived in narrow biological terms but in ‘wide’ terms permitting biological, cultural and technological relations of descent between human and posthuman. Finally, I consider the ethical implications of this metaphysics of the posthuman. If, as I claim, the posthuman difference is not one between kinds but between individuals, we cannot specify its nature a priori but only a posteriori. Thus the only way to evaluate the posthuman condition would be to witness the emergence of posthumans. The implications of this are somewhat paradoxical. We are not currently in a position to evaluate the posthuman condition. Since there are no posthumans, the condition of posthumanity is not defined. However, posthumans could result from some iteration of our current technical activity, so we have an interest in understanding what they might be like. It follows that we have an interest in making or becoming posthumans. (shrink)

Contrary to widely shared opinion in analytic metaphysics, E.J. Lowe argues against the existence of relations in his posthumously published paper There are probably no relations (2016). In this article, I assess Lowe’s eliminativist strategy, which aims to show that all contingent “relational facts” have a monadic foundation in modes characterizing objects. Second, I present two difficult ontological problems supporting eliminativism about relations. Against eliminativism, metaphysicians of science have argued that relations might well be needed in the best a (...) class='Hi'>posteriori motivated account of the structure of reality. Finally, I argue that, by analyzing relational inherence, trope theory offers us a completely new approach to relational entities and avoids the hard problems motivating eliminativism. (shrink)

In a lot of domains in metaphysics the tacit assumption has been that whichever metaphysical principles turn out to be true, these will be necessarily true. Let us call necessitarianism about some domain the thesis that the right metaphysics of that domain is necessary. Necessitarianism has flourished. In the philosophy of maths we find it held that if mathematical objects exist, then they do of necessity. Mathematical Platonists affirm the necessary existence of mathematical objects (see for instance Hale and Wright (...) 1992 and 1994; Wright 1983 and 1988; Schiffer 1996; Resnik 1997; Shapiro 1997 and Zalta 1988) while mathematical nominalists, usually in the form of fictionalists, hold that necessarily such objects fail to exist (see for instance Balaguer 1996 and 1998; Rosen 2001 and Yablo 2005). In metaphysics more generally, until recently it was more or less assumed that whatever the right account of composition—the account of under what conditions some xs compose a y—that account will be necessarily true (for a discussion of theories of composition see Simons 1987 and van Inwagen 1987 and 1990; the modal status of the composition relation is explicitly addressed in Schaffer 2007; Parsons 2006 and Cameron 2007). Similarly, it has generally been assumed that whatever the right account is of the nature of properties, whether they be universals, tropes, or whether nominalism is true, that account will be necessarily true (though see Rosen 2006 for a recent suggestion to the contrary). In considering theories of persistence it has been widely held that whether objects endure or perdure through time is a matter of necessity (Sider 2001; though see Lewis 1999 p227 who defends contingent perdurantism). And with respect to theories of time it is frequently held that whichever of the A- or B-theory is true is necessarily true. A-theorists often argue that there is time in a world only if the A-theory is true at that world (see for instance McTaggart 1903; Markosian 2004; Bigelow 1996; Craig 2001) while B-theorists often argue that the A-theory is internally inconsistent (Smart 1987; Mellor 1998; Savitt 2000 and Le Poidevin 1991). Once again, we find a few recent contingentist dissenters. Bourne (2006) suggests that it is a contingent feature of time that it is tensed, and thus that the A-theory is contingently true. Worlds in which there exist only B-theoretic properties are worlds with time, it is just that time in those worlds time is radically different to the way it is actually. Other defenders of the B-theory, though not expressly contingentists, do offer arguments against versions of the A-theory that try to show that such A-theories theories are inconsistent with the actual laws of nature (see for instance Saunders 2002 and Callender 2000); these arguments, at least, leave room for the possibility that the A-theories in question are contingently false (at least on the assumption that the laws of nature are themselves contingent, an assumption that not everyone accepts). Despite some notable exceptions, necessitarianism has flourished in many, if not most, domains in metaphysics. One such exception is Lewis’ famous defence of Humean supervenience as a contingent claim about our world. Lewis does not argue that necessarily, the supervenience base for all matters of fact in a world is nothing but a vast mosaic of local matters of particular fact. Rather, he thinks that we have reason to think that our world is one in which Humean supervenience holds (see Lewis 1986 p9-10 and 1994). Another exception to the necessitarian orthodoxy is to be found in the lively debate about the modal status of the laws of nature. Here, if anything, contingentism has been the dominating force, with it generally being held that there are possible worlds in which different laws of nature hold (this view is defended by, among others, Lewis 1986 and 2010; Schaffer 2005 and Sidelle 2002). Necessitarian dissenters hold that the laws of nature are necessary, frequently because they think it is necessary that fundamental properties have the causal or nomic profiles they do (see for instance Shoemaker 1980 and 1988; Swoyer 1982; Bird 1995; Ellis and Lierse 1994). Nevertheless, when it comes to thinking about the nature of the laws themselves, the necessitarian presumption is back on firm footing. Though there is disagreement about whether the laws are generalisations that feature in the most virtuous true axiomatisation of all the particular matters of fact (often known as the Humean view of laws and defended by Ramsey 1978; Lewis 1986 and Beebee 2000) or whether laws are relations of necessity that hold between universals (a view defended by Armstrong 1983; Dretske 1977; Tooley 1977 and Carroll 1990) no one has seriously suggested that it might be a contingent matter which of these is the right account of laws. The necessitarian orthodoxy is not surprising since metaphysics is largely an a priori process. While a priori reasoning may be used to determine whether a proposition is necessary or contingent, it is not well placed (in the absence of a posteriori evidence) to determine whether a contingent proposition is actually true or false. Since metaphysicians aim to tell us which principles are true in which worlds, on the face of it the discovery that metaphysical principles are contingent seems to make part of the task of metaphysics epistemically intractable. In what follows I consider two reasons one might end up embracing contingentism and whether this would lead one into epistemic difficulty. The following section considers a route to contingent metaphysical truths that proceeds via a combination of conceptual necessities and empirical discoveries. Section 3 considers whether there might be synthetic contingent metaphysical truths, and the final section raises the question of whether if there were such truths we would be well placed to come to know them. (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)

The identity theory’s rise to prominence in analytic philosophy of mind during the late 1950s and early 1960s is widely seen as a watershed in the development of physicalism, in the sense that whereas logical behaviourism proposed analytic and a priori ascertainable identities between the meanings of mental and physical-behavioural concepts, the identity theory proposed synthetic and a posteriori knowable identities between mental and physical properties. While this watershed does exist, the standard account of it is misleading, as it (...) is founded in erroneous intensional misreadings of the logical positivists’—especially Carnap’s—extensional notions of translation and meaning, as well as misinterpretations of the positivists’ shift from the strong thesis of translation-physicalism to the weaker and more liberal notion of reduction-physicalism that occurred in the Unity of Science programme. After setting the historical record straight, the essay traces the first truly modern identity theory to Schlick’s pre-positivist views circa 1920 and goes on to explore its further development in Feigl, arguing that the fundamental difference between the Schlick-Feigl identity theory and the more familiar and influential Place-Smart-Armstrong identity theory has resurfaced in the deep and seemingly unbridgeable gulf in contemporary philosophy of consciousness between inflationary mentalism and deflationary physicalism. (shrink)

In this chapter, it is suggested that our epistemic access to metaphysical modality generally involves rationalist, a priori elements. However, these a priori elements are much more subtle than ‘traditional’ modal rationalism assumes. In fact, some might even question the ‘apriority’ of these elements, but I should stress that I consider a priori and a posteriori elements especially in our modal inquiry to be so deeply intertwined that it is not easy to tell them apart. Supposed metaphysically necessary identity (...) statements involving natural kind terms are a good example: the fact that empirical input is crucial in establishing their necessity has clouded the role and content of the a priori input, as I have previously argued. For instance, the supposed metaphysically necessary identity statement involving water and its microstructure can only be established with the help of a controversial a priori principle concerning the determination of chemical properties by microstructure. The Kripke-Putnam framework of modal epistemology fails precisely because it is unclear whether the required a priori element is present. My positive proposal builds on E. J. Lowe’s work. Lowe holds that our knowledge of metaphysical modality is based on our knowledge of essence. Lowe’s account strives to offer a uniform picture of modal epistemology: essence is the basis of all our modal knowledge. This is the basis of Lowe’s modal rationalism. I believe that Lowe’s proposal is on the right lines in the case of abstract objects, but I doubt that it can be successfully applied to the case of natural kinds. Accordingly, the case of natural kinds will be my main focus and I will suggest that modal rationalism, at least as it is traditionally understood, falls short of explaining modal knowledge concerning natural kinds. Yet, I think that Lowe has identified something of crucial importance for modal epistemology, namely the essentialist, a priori elements present in our modal inquiry. The upshot is that rather than moving all the way from modal rationalism to modal empiricism, a type of hybrid approach, ‘empirically-informed modal rationalism ’, can be developed. (shrink)

The core doctrine of ethical intuitionism is that some of our ethical knowledge is non-inferential. Against this, Sturgeon has recently objected that if ethical intuitionists accept a certain plausible rationale for the autonomy of ethics, then their foundationalism commits them to an implausible epistemology outside ethics. I show that irrespective of whether ethical intuitionists take non-inferential ethical knowledge to be a priori or a posteriori, their commitment to the autonomy of ethics and foundationalism does not entail any implausible non-inferential (...) knowledge in areas outside ethics (such as the past, the future, or the unobservable). However, each form of intuitionism does require a controversial stand on certain unresolved issues outside ethics. (shrink)

In the following paragraphs, I will describe ten strategies through which we can show the weaknesses of every form of theism, while postulating that the Trinity is a good solution. This approach follows up on Swinburne’s claims about the existence of a priori and a posteriori proofs for the existence of the Trinity (his proofs are part of the sixth strategy). Clearly, these strategies are not “new”: they have been advocated by many thinkers in the past and in the (...) present. I merely revived them, and brought them together in a kind of cumulative reasoning: the strength of the Kantian Argument arises when these strategies are considered together, showing that the Trinity is a reasonable hypothesis even though it is contradictory. (shrink)

We argue that a conflict between two conceptions of “quantity of matter” employed in a corollary to proposition 6 of Book III of the Principia illustrates a deeper conflict between Newton’s view of the nature of extended bodies and the concept of mass appropriate for the theoretical framework of the Principia. We trace Newton’s failure to recognize the conflict to the fact that he allowed for the justification of natural philosophical claims by two types of a posteriori, empiricist methodologies. (...) Newton's thoughts on these methodologies demonstrate that his natural philosophy continued to develop after the publication of the first edition of Principia and that De Grav should be understood as an early, and not necessarily representative, text. (shrink)

This paper defends the traditional view that the laws of nature are contingent, or, if some of them are necessary, this is due to analytic principles for the individuation of the law-governed properties. Fundamentally, I argue that the supposed explanatory purposes served by taking the laws to be necessary --showing how laws support counterfactuals, how properties are individuated, or how we have knowledge of properties--are in fact undermined by the continued possibility of the imagined scenarios--this time, described neutrally--which seemed to (...) disprove the claim to necessity in the first place. I speculate that this will be true for any proposed necessary a posteriori truths, and is a basis for rejecting their supposed metaphysical significance. (shrink)

Metaethical realists disagree about the nature of normative properties. Naturalists think that they are ordinary natural properties: causally efficacious, a posteriori knowable, and usable in the best explanations of natural and social sciences. Non-naturalist realists, in contrast, argue that they are sui generis: causally inert, a priori knowable and not a part of the subject matter of sciences. It has been assumed so far that naturalists can explain causally how the normative predicates manage to refer to normative properties, whereas (...) non-naturalists are unable to provide equally satisfactory metasemantic explanations. This article first describes how the previous non-naturalist accounts of reference fail to tell us how the normative predicates could have come to refer to the non-natural properties rather than to the natural ones. I will then use the so-called qua-problem to show how the causal theories of reference of naturalists also fail to fix the reference of normative predicates to unique natural properties. Finally, I will suggest that, just as naturalists need to rely on the non-causal mechanism of reference magnetism to solve the previous problem, non-naturalists, too, can rely on the very same idea to respond to the pressing metasemantic challenges that they face concerning reference. (shrink)