A serious crisis is identified in theories of neurocomputation, marked by a persistent disparity between the phenomenological or experiential account of visual perception and the neurophysiological level of description of the visual system. In particular, conventional concepts of neural processing offer no explanation for the holistic global aspects of perception identified by Gestalt theory. The problem is paradigmatic and can be traced to contemporary concepts of the functional role of the neural cell, known as the Neuron Doctrine. In the absence (...) of an alternative neurophysiologically plausible model, I propose a perceptual modeling approach, to model the percept as experienced subjectively, rather than modeling the objective neurophysiological state of the visual system that supposedly subserves that experience. A Gestalt Bubble model is presented to demonstrate how the elusive Gestalt principles of emergence, reification, and invariance can be expressed in a quantitative model of the subjective experience of visual consciousness. That model in turn reveals a unique computational strategy underlying visual processing, which is unlike any algorithm devised by man, and certainly unlike the atomistic feed-forward model of neurocomputation offered by the Neuron Doctrine paradigm. The perceptual modeling approach reveals the primary function of perception as that of generating a fully spatial virtual-reality replica of the external world in an internal representation. The common objections to this picture-in-the-head concept of perceptual representation are shown to be ill founded. Key Words: brain-anchored; Cartesian theatre; consciousness; emergence; extrinsic constraints; filling-in; Gestalt; homunculus; indirect realism; intrinsic constraints; invariance; isomorphism; multistability; objective phenomenology; perceptual modeling; perspective; phenomenology; psychophysical parallelism; psychophysical postulate; qualia; reification; representationalism; structural coherence. (shrink)

The Gestalt principle of isomorphism reveals the primacy of subjective experience as a valid source of evidence for the information encoded neurophysiologically. This theory invalidates the abstractionist view that the neurophysiological representation can be of lower dimensionality than the percept to which it gives rise.

Naïve realism, the view that perceptual experiences are irreducible relations between subjects and external objects, has intuitive appeal, but this intuitive appeal is sometimes thought to be undermined by the possibility of certain kinds of hallucinations. In this paper, I present the intuitive case for naïve realism, and explain why this intuitive case is not undermined by the possibility of such hallucinations. Specifically, I present the intuitive case for naïve realism as arguing that the only way to make sense of (...) the phenomenal character associated with perceptual experiences is by means of a naïve realist ontology. I then explain why this intuitive argument is not undermined by the possibility of hallucinatory experiences that possess the phenomenal character associated with perceptual experiences but, being hallucinations, do not have the ontological nature specified by naïve realism. (shrink)

Gilbert Ryle’s distinction between knowledge-how and knowledge-that emerged from his criticism of the “intellectualist legend” that to do something intelligently is “to do a bit of theory and then to do a bit of practice,” and became a philosophical commonplace in the second half of the last century. In this century Jason Stanley has attacked Ryle’s distinction, arguing that “knowing-how is a species of knowing-that,” and accusing Ryle of setting up a straw man in his critique of “intellectualism.” Examining the (...) use of the terms “intellectualism” and “anti-intellectualism” in the first half of the 20th century, in a wide-ranging debate in the social sciences as well as in philosophy, I show that Ryle was not criticizing a straw man, but a live historical position. In the context of this controversy, Ryle’s position represents a third way between “intellectualism” and “anti-intellectualism,” an option that has largely gone missing in the 21st century discussion. This argument illustrates how history can inform the history of philosophy, and how the history of philosophy can inform contemporary philosophical inquiry. (shrink)

Colors are sensible qualities. They are qualities that objects are perceived to have. Thus, when Norm, a normal perceiver, perceives a blue bead, the bead is perceived have a certain quality, perceived blueness. `Quality', here, is no mere synonym for property; rather, a quality is a kind of property a qualitative, as opposed to quan• titative, property. (The quantitative is a way of contrasting with the qualitative perhaps not the only way.).

For some years now, an increasing number of philosophers have been holding that what is given in perception are the physical objects of our surroundings. This is the view called, among others names, “the Relational View”. Basically, this view consists in the claim that experience is not representational, it is not a matter of the subject's taking things in the world to be this or that way; rather, it is just a matter of being presented with things, of being in (...) a certain kind of relation with them, which makes them available to us, nevertheless, to be represented in judgement or belief. The question arises, however, whether this does not imply a new fall into the Myth of the Given. In this article, I argue for an affirmative response to that question. (shrink)

The verb ‘to know’ can be used both in ascriptions of propositional knowledge and ascriptions of knowledge of acquaintance. In the formal epistemology literature, the former use of ‘know’ has attracted considerable attention, while the latter is typically regarded as derivative. This attitude may be unsatisfactory for those philosophers who, like Russell, are not willing to think of knowledge of acquaintance as a subsidiary or dependent kind of knowledge. In this paper we outline a logic of knowledge of acquaintance in (...) which ascriptions like ‘Mary knows Smith’ are regarded as formally interesting in their own right, remaining neutral on their relation to ascriptions of propositional knowledge. The resulting logical framework, which is based on Hintikka’s modal approach to epistemic logic, provides a fresh perspective on various issues and notions at play in the philosophical debate on acquaintance. (shrink)

Externalist representationalism is touted as a superior rival to naïve realism, and yet a careful analysis of the externalist representationalist's analysis of our ordinary perceptual experiences shows the view to be far closer to naïve realism than we might have expected. One of the central advertised benefits of representationalist views in general is that they are compatible with the idea that ordinary, illusory and hallucinatory perceptual experiences are of the same fundamental kind. Naïve realists are forced to deny the ‘common (...) fundamental kind claim’ and adopt disjunctivism. However, I argue that externalist representationalism is also a version of disjunctivism. Consequently, one of the main rivals to naïve realism turns out not to be a rival at all. (shrink)

What method should we use to determine the nature of perceptual experience? My focus here is the Kantian thought that transcendental arguments can be used to determine the nature of perceptual experience. I set out a dilemma for the use of transcendental arguments in the philosophy of perception, one which turns on a comparison ofthe transcendental method with the first-personal method of early analytic philosophy, and with the empirical methods of much contemporary philosophy of mind. The transcendental method can avoid (...) this dilemma only if it commits to our possessing a capacity for imaginative reflection, one which is capable of identifying certain formal properties of experience.This result indicates some of the commitments which must be made if transcendental arguments are to be used in the philosophy of perception, and it has implications for those views that take the philosophy of perception to be autonomous of the empirical science of perception. (shrink)

Proponents of the causal theory of perception have applied the theory to questions about which particular objects or events are perceived, which parts are perceived, and which properties are perceived. In each case they insist that successful perception is causally dependent on what is perceived. The causal theory rests on an important insight regarding the information-carrying role of perception. In order to succeed in this role, perception cannot be grounded in spurious correlations. But we can respect this insight without embracing (...) the idea that a successful percept must be causally dependent on what is perceived. A correlation in nature can also be genuine or lawful when it arises from a common cause. I show how successful perception is frequently achieved through correlation via a common cause. (shrink)

Monists say that the nature of truth is invariant, whichever sentence you consider; pluralists say that the nature of truth varies between different sets of sentences. The orthodoxy is that logic and logical form favour monism: there must be a single property that is preserved in any valid inference; and any truth-functional complex must be true in the same way as its components. The orthodoxy, I argue, is mistaken. Logic and logical form impose only structural constraints on a metaphysics of (...) truth. Monistic theories are not guaranteed to satisfy these constraints, and there is a pluralistic theory that does so. (shrink)

This paper trials new experimental methods for the analysis of natural language reasoning and the development of critical ordinary language philosophy in the wake of J.L. Austin. Philosophical arguments and thought experiments are strongly shaped by default pragmatic inferences, including stereotypical inferences. Austin suggested that contextually inappropriate stereotypical inferences are at the root of some philosophical paradoxes and problems, and that these can be resolved by exposing those verbal fallacies. This paper builds on recent efforts to empirically document inappropriate stereotypical (...) inferences that may drive philosophical arguments. We demonstrate that previously employed questionnaire-based output measures do not suffice to exclude relevant confounds. We then report an experiment that combines reading time measurements with plausibility ratings. The study seeks to provide evidence of inappropriate stereotypical inferences from appearance verbs that have been suggested to lie at the root of the influential ‘argument from illusion’. Our findings support a diagnostic reconstruction of this argument. They provide the missing component for proof of concept for an experimental implementation of critical ordinary language philosophy that is in line with the ambitions of current ‘evidential’ experimental philosophy. (shrink)

Intuitive judgments elicited by verbal case-descriptions play key roles in philosophical problem-setting and argument. Experimental philosophy's ‘sources project’ seeks to develop psychological explanations of philosophically relevant intuitions which help us assess our warrant for accepting them. This article develops a psycholinguistic explanation of intuitions prompted by philosophical case-descriptions. For proof of concept, we target intuitions underlying a classic paradox about perception, trace them to stereotype-driven inferences automatically executed in verb comprehension, and employ a forced-choice plausibility-ranking task to elicit the relevant (...) stereotypical associations of perception- and appearance-verbs. We obtain a debunking explanation that resolves the philosophical paradox. (shrink)

Many philosophical debates take for granted that there is such a thing as ‘the’ common-sense conception of the phenomenon of interest. Debates about the nature of perception tend to take for granted that there is a single, coherent common-sense conception of vision, consistent with Direct Realism. This conception is often accorded an epistemic default status. We draw on philosophical and psychological literature on naïve theories and belief fragmentation to motivate the hypothesis that untutored common sense encompasses conflicting Direct Realist and (...) Indirect Realist conceptions: there is no such thing as ‘the’ common-sense conception of vision that could enjoy epistemic default status. To examine this hypothesis, a survey administered an agreement rating task with verbal and pictorial stimuli to lay participants. We found many laypeople simultaneously hold conflicting Direct Realist and Indirect Realist beliefs about vision. Against common assumptions, Direct Realist beliefs are not clearly dominant, and consistent adherence to Direct Realism is not the norm, but the exception. These findings are consistent with recent accounts of belief fragmentation. They forcefully challenge common methodology in philosophical debates about the nature of perception and beyond. (shrink)

To be acquainted with something (in the philosophical sense of “acquainted” discussed here) is to be directly aware of it. The idea that we are acquainted with certain things we experience has been discussed throughout the history of Western Philosophy, but in the early 20th century it gained especially focused attention among analytic philosophers who drew their inspiration from Bertrand Russell's work on acquaintance. Since then, many philosophers—particularly those working on self‐knowledge or perception—have used the notion of acquaintance to explain (...) various facts about human experience and knowledge. In this paper, I offer an overview of this work, with particular focus on the resurgent literature on acquaintance in contemporary analytic philosophy. After more fully explaining what acquaintance is (or is supposed to be), I describe some reasons for thinking that we are indeed acquainted with certain things we experience, and then I survey some of the facts about experience and knowledge that acquaintance may help explain. (shrink)

In this paper we set out a view on which internalist proper basicality is secured by sensory experience.

I raise some objections to the theory presented in *Outside Color*.

We begin with a theory of the structure of sensory consciousness; a target phenomenon of 'presentation' can be clearly located within this structure. We then defend the rational-psychological necessity of presentation. We conclude with discussion of these philosophical challenges to the possibility of presentation. One crucial aspect of the discussion is recognition of the <cite>nonobjectivity</cite> of consciousness (a technical appendix explains what I mean by that). The other is a full-faced stare at the limitations of rational psychology: much of the (...) dialectic in the philosophy of perception pertains to matters beyond the limits of coherence---a breakwater against which philosophy crashes, and rolls back. (shrink)

My main aim is to clarify what we mean by ‘look’ sentences such as (1) below – ones that we use to talk about visual experience: -/- (1) The ball looked red to Sue -/- This is to help better understand a part of natural language that has so far resisted treatment, and also to help better understand the nature of visual experience. -/- By appealing to general linguistic principles I argue for the following account. First, we use (1) to (...) talk about an event. Second, we use the verb ‘look’ to specify the kind of event about which we are talking – it is a looking event. Third, we use the subject ‘the ball’ to specify a stimulus of the event – something that looks some way in the event. Fourth, we use the adjunct ‘to Sue’ to specify an experiencer of the event – someone to whom things look some way in the event. Finally, we use the complement ‘red’ to specify a way of the event – a way in which the event occurs (I take ways of occurring to be properties of events). Which way do we use ‘red’ in (1) to specify? I argue: the maximally specific way w such that the following is generically true: looking events whose stimulus is red occur in way w (it is important that this is understood generically: this is what does much of the work in explaining our use of (1) and other ‘look’ sentences). Putting this together, what we mean by (1) is: there was a looking event whose stimulus was the ball, whose experiencer was Sue, and which occurred in the maximally specific way that looking events occur when their stimulus is red. -/- This account of how we use ‘red’ in (1) is one of the most interesting aspects of my thesis. It extends to an account of how we use ‘proud’ in ‘John walks proud’, ‘as if he is American’ in ‘John talks as if he is American’, ‘like a duck’ in ‘John sounds like a duck’, and so on. In each case we use the expression in question to specify a way: the maximally specific way proud people walk, the maximally specific way American people talk, and so on. So the study of ‘look’ sentences has much to tell us about the functioning of many other English language constructions, and suggests that ways have a significant role to play in the semantics of natural language – a fact that has not yet been sufficiently recognised by linguists or philosophers of language. -/- My thesis also has implications for the philosophy of perception. One of the central questions about perception is: What is the nature of visual experience? What is it, for example, for a ball to look red to Sue? My thesis offers an answer: What it is for the ball to look red to Sue is for whatever it is that we mean by ‘The ball looks red to Sue’ to be the case, and what we mean by ‘The ball looks red to Sue’ is that there is a looking event whose stimulus is the ball, whose experiencer is Sue, and which is occurring in a certain way. It thus delivers an adverbial account of visual experience, one that has the resources to better deal with problems that are traditionally thought to be decisive against adverbial accounts. (shrink)

The debate between relationalism and representationalism in the philosophy of perception seems to have come to a standstill where opponents radically disagree on methodological principles or fundamental assumptions. According to Fish (this volume) this is because, not unlike Kuhnian scientific paradigms, the debate displays some elements of incommensurability. This diagnosis makes advancing the debate impossible. I argue that what is hindering progress is not a clash of research programmes, but a series of misunderstandings that can be avoided by disentangling the (...) different questions each theory is invested in and by making explicit the hidden assumptions at play in the debate. One such central assumption is what I call the Superficiality Constraint. This is the idea that the phenomenal character of experience is superficial with respect to introspection. I argue that we can make progress in the debate by assessing to what extent and at what cost relationalism can accommodate this constraint. (shrink)

Content disjunctivism is the view that veridical experience involves contents and objects that differ from those of corresponding hallucinations. On one formulation of this view, we are aware of ordinary material things in our surroundings when we experience veridically, and we are aware of mere appearances when we hallucinate. This paper proposes a way of developing this view and offers some considerations in support. Central to the proposed regimentation will be a distinction between different notions of appearance. We distinguish between (...) the notion of something merely appearing to have a property and the notion of mere appearances, which are types of objects that we can refer to and be aware of. Mere appearances are not sense data or Meinongian non-existent objects but existing objects that do not have the properties that they appear to have. These notions of appearance will be elucidated, in particular by characterizing how they are involved in hallucination and illusion. I argue that the resulting view is supported by how our mental life seems to us when we experience our environment. (shrink)

In the philosophy of perception, direct realism has come into vogue. Philosophical authors assert and assume that what their readers want, and what anyone should want, is some form of direct realism. There are disagreements over precisely what form this direct realism should take. The majority of positions in favor now offer a direct realism in which objects and their material or physical properties constitute the contents of perception, either because we have an immediate or intuitive acquaintance with those objects (...) and properties, or because our perceptual states have informational content that represents the properties of those objects (and which is not itself an object of perception and has no specifically subjective aspect). This paper considers various forms of perceptual realism, including, for purposes of comparison, the largely abandoned indirect or representative realism. After surveying the variety of perceptual realisms and considering their various commitments, I introduce some considerations concerning the phenomenology of visual space that cause trouble for most forms of direct realism. These considerations pertain to the perception of objects in the distance and, secondarily, to the perception of shapes at a slant. I argue that one of the lesser known varieties of perceptual realism, critical direct realism, can meet the challenges offered by the facts of spatial perception. (shrink)

In his book “Seeing Dark Things” (2008), Roy Sorensen provides many wonderfully ingenious arguments for many surprising, counter-intuitive claims. One such claim in particular is that when we a silhouetted object – i.e. an opaque object lit entirely from behind – we literally see its back-side – i.e. we see the full expanse of the surface facing away from us that is blocking the incoming light. Sorensen himself admits that this seems a tough pill to swallow, later characterising it as (...) “the most controversial thesis of the book” (2011, p199). -/- I will argue against Sorensen’s controversial thesis and in favour of what seems to me to be a much more natural and commonsensical alternative: when we see a silhouetted object, what we see is its edge and only its edge – so we do not see its entire back-side. (shrink)

Consider three answers to the question of what it actually is for you to be aware of the room you are in. It is for the room in a way to exist. It is for there to be only physical activity in your head, however additionally described. It is for there to be non-spatial facts somehow in your head. The first theory, unlike the other two, satisfies five criteria for an adequate account of consciousness itself. The criteria have to do (...) with the seeming nature of this consciousness, and with subjectivity, reality including non-abstractness, mind-body causation, and the differences between perceptual, reflective and affective consciousness. The theory of consciousness as existence is not open to the objection having to do with a deluded brain in a vat. The theory, as any theory of consciousness needs to, explains its own degree of failure in characterizing consciousness. It releases neuroscience and cognitive science from nervousness about consciousness, and leaves all of consciousness a subject for science. The theory is a reconstruction of our conception of consciousness. It may be that we should carry forward several theories of consciousness. But they will have to be compared in terms of truth to the five criteria for an adequate theory. (shrink)

How do I know that I see a cat? A curiously under-asked question. The paper tries to answer it.

My dissertation is a systematic defense of the claim that what it is to be rational is to correctly respond to the reasons you possess. The dissertation is split into two parts, each consisting of three chapters. In Part I--Coherence, Possession, and Correctly Responding--I argue that my view has important advantages over popular views in metaethics that tie rationality to coherence (ch. 2), defend a novel view of what it is to possess a reason (ch. 3), and defend a novel (...) view about what it is to act and hold attitudes for normative reasons (ch. 4). In Part II--Foundationalism, Deception, and The Importance of Being Rational--I argue that foundationalists about epistemic rationality should think that the foundational beliefs are held for sufficient reasons (ch. 5), argue that my view solves the New Evil Demon problem for externalism (and solves a related and underapprieciated problem) (ch. 6), and argue that my view can vindicate the thought that we ought to be rational (ch. 7). (shrink)

Ci imbattiamo in un confine ogni volta che pensiamo a un’entità demarcata rispetto a ciò che la circonda. C’è un confine (una superficie) che delimita l’interno di una sfera dal suo esterno; c’è un confine (una frontiera) che separa il Maryland dalla Pennsylvania. Talvolta la collocazione esatta di un confine non è chiara o è in qualche modo controversa (come quando si cerchi di tracciare i limiti del monte Everest, o il confine del nostro corpo). Talaltra il confine non corrisponde (...) a una discontinuità fisica o a una differenziazione qualitativa (come nel caso dei confini del Wyoming, o della demarcazione tra la metà superiore e la metà inferiore di una sfera omogenea). Ma, che sia netto o confuso, naturale o artificiale, sembra esservi per ogni oggetto un confine che lo separa dal resto del mondo. Anche gli eventi hanno confini, quantomeno confini temporali. Le nostre vite sono delimitate dalle nostre nascite e morti; una partita di calcio comincia alle quindici in punto e termina col fischio finale dell’arbitro alle sedici e quarantacinque. E a volte si dice che anche le entità astratte, come i concetti o gli insiemi, hanno dei propri confini. Se tutto questo parlare di confini abbia davvero un senso, e se rifletta la struttura del mondo o solo l’attività organizzatrice del nostro intelletto, è però oggetto di profonda controversia filosofica. (shrink)

What is the distinctively philosophical problem of perception? Here it is argued that it is the conflict between the nature of perceptual experience as it intuitively seems to us, and certain possibilities which are implicit in the very idea of experience: possibilities of illusion and to the world' which involves direct awareness of existing objects and their properties. But if one can have an experience of the same kind without the object being there -- a hallucination of an object -- (...) then it seems that perceptual experience cannot essentially be such a relation. This is the fundamentally philosophical problem of perception; the various philosophical theories of perception in the 20th and 21st centuries can be seen as responses to it. (shrink)

Since the demise of the Sense-Datum independent objects or events to be objects Theory and Phenomenalism in the last cenof perception; however, unlike Direct Retury, Direct Realism in the philosophy of alists, Indirect Realists take this percepperception has enjoyed a resurgence of tion to be indirect by involving a prior popularity.1 Curiously, however, although awareness of some tertium quid between there have been attempts in the literature the mind and external objects or events.3 to refute some of the arguments against (...) Idealists and Phenomenalists agree with Direct Realism, there has been, as of yet, the Indirect Realists. (shrink)

This dissertation proposes the central elements of a Social Enactive Theory of Perception. According to SEP, perception consists in sensory-based practices of interaction with objects, events, and states of affairs that are socially constituted. I oppose the representational view that perception is an indirect contact with the world, consists of the passive receiving and processing of sensory input, is in need of constant assessment of accuracy, and is a matter of individuals alone. I share the basic enactivist insight that perception (...) is a type of activity, but I depart from standard enactivism on the grounds of its individualistic bias and its limited conception of activity. Instead of motor actions, I formulate the concept of perceptual practices as the appropriate framework to understand perception. Perception is woven into socially informed, contextual, sensory-based everyday activities, such as food, dance, and dress, and even seemingly independent, basic perceptual activities and concepts are constituted by such practices. Perceptual individual interactions instantiate social perceptual practices but are not just repetitions of a script. We perceive objects in virtue of perspectives or appearances, not in spite of them, and on this basis I offer SEPâs take on experience, properties, and contents. I conceive perceptual experience as finely grained interactions between subjects and objects, both of which are spatially, temporally, and pragmatically situated. Objects and their sensory properties are perceived dynamically and always in multiple appearances. Perceptual content offers a pragmatic specification of the perceptual objects in the specific ways they appear to subjects. For SEP, perception is normatively structured. SEPâs perceptual normativity is not a worry about a supposed constant threat that our perceptions be nonveridical, but about the placement of perceptual things in a system of possibilities and expectations, cast in terms of degrees of fulfillment of expectations and in a horizon of pragmatic significance, both of which are functions of the socially constituted interactions between a perceiver and a rich theory of appearances. (shrink)

Many of our ordinary beliefs about the world around us are a result of inference from more fundamental beliefs. Foundationalists in epistemology have thought that, if these ordinary beliefs are to be rationally justified, the chain of inferential justification must terminate in a belief that is justified noninferentially. Foundationalists, of the internalist variety, have thought that the most plausible candidates for ending the regress of empirical justification are experiential states, the justifying features of which the believing subject is aware. The (...) Sellarsian dilemma, taking its name from philosopher Wilfrid Sellars, has been a persistent argument against foundationalist theories of epistemic justification. There have been various formulations of the dilemma over the years, but in its most general form it says that for any construal of an experiential state where the experiential state provides justification, the experiential state will need further justification. Sellars thought that an experience, all by itself, cannot provide justification unless we apply concepts to the experience. However, the application of concepts is judgmental and conceptual judgments, like beliefs, require further justification. So, the experiential state construed this way would perpetuate the regress it was designed to terminate. On the other hand, if the experiential state is construed such that it is not in need of justification, then it cannot itself provide justification. Both options are devastating to a foundationalist epistemology. My thesis is that a solution to all forms of the Sellarsian dilemma is to require for foundational justification direct awareness of the fit between one's conceptual judgment and the justifying experiential state. I concede that one must conceptualize one's experiential states for these states to play an epistemic role. However, I argue that conceptual judgments of this sort are the foundations. The importance of this solution is that it not only terminates the regress of justification but it also captures the primary intuitions that motivate internalism and foundationalism. This is to say that although I have framed my account as a response to the Sellarsian dilemma, it is not merely an ad hoc patch that avoids what stood as a serious problem. Instead, it is a return to what has motivated and what I take to be most persuasive about internalist foundationalism. (shrink)

Defenders of the Knowledge Argument contend that physicalism is false because knowing all the physical truths is not sufficient to know all the truths about the world. In particular, proponents of the Knowledge Argument claim that physicalism is false because the truths about the character of conscious experience are not knowable from the complete set of physical truths. This dissertation is a defense of the Knowledge Argument. Chapter one characterizes what physicalism is and provides support for the claim that if (...) knowing all the physical truths is not sufficient to know all the truths about the world, then physicalism is false. In chapter two, I defend the claim that knowing all the physical truths is not sufficient for knowing all the truths about the world. In addition to mounting a prima facie case for the knowledge intuition, I present and defend an epistemology grounded in direct acquaintance to provide a more substantive argument to accept it. Chapters three through five address the physicalist objections to the Knowledge Argument. The first set of objections advocates that knowing all the physical truths is, in fact, sufficient for knowing all the truths about the world. The next set of objections admits that there is some sense in which knowing all the physical truths is not sufficient for knowing all the truths about the world. However, these objections maintain that the kind of knowledge that is absent from the complete set of physical truths is know-how or knowledge by acquaintance, and not factual or propositional knowledge. The final set of objections maintain that the kind of propositional knowledge that is left out of the complete set of physical truths is compatible with physicalism. My response to these objections is part of advancing my prima facie case for the Knowledge Argument. The final chapter addresses a structural question that pertains to the Knowledge Argument. Some philosophers have maintained that the structure of the Knowledge Argument invites a kind of self-refutation of any systematic account of reality. The concern is that the Knowledge Argument proves too much, and that the dualist who uses the argument to refute physicalism risks the argument defeating his own position. I will argue that the Knowledge Argument does not refute dualism. (shrink)