It is commonly held that the experiences involved in cases of perception, illusion and hallucination all have the same nature. Disjunctivists deny this. They maintain that the kind of experience you have when you perceive the world isn’t one you could be having if you were hallucinating. A number of important debates in the philosophy of mind and epistemology turn on the question of whether this disjunctivist view is tenable. This is the first book-length introduction to this contested issue. Matthew (...) Soteriou explains the accounts of perception that disjunctivists seek to defend, such as naïve realism, and the accounts to which they are opposed, such as sense-datum theories and representationalist theories. He goes on to introduce and assess key questions that arise in these debates: Is disjunctivism consistent with what has been established by the science of perception? Does introspective reflection support naïve realism? Can disjunctivism be motivated by appeal to the role that perception plays in enabling us to think demonstratively about mind-independent objects and qualities in our environment? Does disjunctivism offer the best account of perceptual knowledge? What can disjunctivists say about the nature of hallucination and illusion? Including chapter summaries, annotated further reading and a glossary, this book is an ideal starting point for anyone studying disjunctivism for the first time, as well as for more advanced students and researchers. (shrink)

This textbook on vision reflects the integrated computational approach of modern research scientists, combining psychological, computational and neuroscientific perspectives.

Naive realists hold that experience is to be understood in terms of an intimate perceptual relation between a subject and aspects of the world, relative to a certain standpoint. Those aspects of the world themselves shape the contours of consciousness. But blurriness is an aspect of some of our experiences that does not seem to come from the world. I argue that this constitutes a significant challenge to some forms of naive realism. But I also argue that there is a (...) robust form of naive realism which is unfazed by the blurriness of some of our experiences, even when that blurriness is understood as a subjective modification of consciousness. (shrink)

Much of the discussion of Naive Realism about veridical experience has focused on a consequence of adopting it—namely, disjunctivism about perceptual experience. However, the motivations for being a Naive Realist in the first place have received relatively little attention in the literature. In this paper, I will elaborate and defend the claim that Naive Realism provides the best account of the phenomenal character of veridical experience.

I raise a problem for common-factor theories of experience concerning the demonstrative thoughts we form on the basis of experience. Building on an insight of Paul Snowdon 1992, I argue that in order to demonstratively refer to an item via conscious awareness of a distinct intermediary the subject must have some understanding that she is aware of a distinct intermediary. This becomes an issue for common-factor theories insofar as it is also widely accepted that the general, pre-philosophical or ‘naïve’ view (...) of experience does not accept that in normal perceptual cases one is consciously aware of non-environmental (inner, mental) features. I argue then that the standard common-factor view of experience should be committed to attributing quite widespread referential errors or failures amongst the general, nonphilosophical populace – which seems an unattractively radical commitment. After clarifying the various assumptions I am making about experience and demonstrative thoughts, I consider a number of possible responses on behalf of the common-factor theorist. I finish by arguing that my argument should apply to any common-factor theory, not just avowedly ‘indirect' theories. (shrink)

This chapter develops a simple theory of introspection on which a mental state is introspectively accessible just by virtue of the fact that one is in that mental state. This theory raises two questions: first, a generalization question: which mental states are introspectively accessible; and second, an explanatory question: why are some mental states introspectively accessible, rather than others, or none at all? In response to the generalization question, I argue that a mental state is introspectively accessible if and only (...) if it is phenomenally individuated. And in response to the explanatory question, I argue that a mental state is introspectively accessible if and only if it is among the determinants of justification. This provides the basis of an argument for a phenomenal conception of justification, according to which a mental state is among the determinants of justification if and only if it is phenomenally individuated. (shrink)

In the first monograph in this exciting area since then, William Fish develops a comprehensive disjunctive theory, incorporating detailed accounts of the three ...

Recently representationalists have cited a phenomenon known as the transparency of experience in arguments against the qualia theory. Representationalists take transparency to support their theory and to work against the qualia theory. In this paper I argue that representationalist assessment of the philosophical importance of transparency is incorrect. The true beneficiary of transparency is another theory, naïve realism. Transparency militates against qualia and the representationalist theory of experience. I describe the transparency phenomenon, and I use my description to argue for (...) naïve realism and against representationalism and the qualia theory. I also examine the relationship between phenomenological study and phenomenal character, and discuss the results in connection with the argument from hallucination. (shrink)

A common objection to sense-datum theories of perception is that they cannot give an adequate account of the fact that introspection indicates that our sensory experiences are directed on, or are about, the mind-independent entities in the world around us, that our sense experience is transparent to the world. In this paper I point out that the main force of this claim is to point out an explanatory challenge to sense-datum theories.

Like dreaming, hallucination has been a formative trope for modern philosophy. The vivid, often tragic, breakdown in the mind’s apparent capacity to disclose reality has long served to support a paradoxical philosophical picture of sensory experience. This picture, which of late has shaped the paradigmatic empirical understanding the senses, displays sensory acts as already complete without the external world; complete in that the direct objects even of veridical sensory acts do not transcend what we could anyway hallucinate. Hallucination is thus (...) the mother of Representationalism, which insists that it is mental intermediaries that make other.. (shrink)

In the Garden of Eden, we had unmediated contact with the world. We were directly acquainted with objects in the world and with their properties. Objects were simply presented to us without causal mediation, and properties were revealed to us in their true intrinsic glory.

The disjunctive theory of perception claims that we should understand statements about how things appear to a perceiver to be equivalent to statements of a disjunction that either one is perceiving such and such or one is suffering an illusion (or hallucination); and that such statements are not to be viewed as introducing a report of a distinctive mental event or state common to these various disjoint situations. When Michael Hinton first introduced the idea, he suggested that the burden of (...) proof or disproof lay with his opponent, that what was needed was to show that our talk of how things look or appear to one.. (shrink)

In the eyes of some of its critics, disjunctivism fails to support adequately the key claim that a particular hallucination might be indistinguishable from a certain kind of veridical perception despite the two states having nothing other than this in common. Scott Sturgeon, for example, has complained that disjunctivism ‘‘offers no positive story about hallucination at all’’ (2000: 11) and therefore ‘‘simply takes [indistinguishability] for granted’’ (2000: 12). So according to Sturgeon, what the disjunctivist needs to provide is a plausible (...) explanation of just how two mental states which have no common component might be indistinguishable for their subject and this in turn will require the telling of a positive story about hallucination. This is the goal of the present essay. (shrink)

Disjunctivism about perceptual appearances, as I conceive of it, is a theory which seeks to preserve a naïve realist conception of veridical perception in the light of the challenge from the argument from hallucination. The naïve realist claims that some sensory experiences are relations to mind-independent objects. That is to say, taking experiences to be episodes or events, the naïve realist supposes that some such episodes have as constituents mind-independent objects. In turn, the disjunctivist claims that in a case of (...) veridical perception like this very kind of experience that you now have, the experiential episode you enjoy is of a kind which could not be occurring were you having an hallucination. The common strategy of arguments from hallucination set out to show that certain things are true of hallucinations, and hence must be true of perceptions. For example, it is argued that hallucinations must have non-physical objects of awareness, or that such states are not relations to anything at all, but are at best seeming relations to objects. In insisting that veridical perceptual experience is of a distinct kind from hallucination, the disjunctivist denies that any of these conceptions of hallucination challenges our conception of veridical perceptions as relations to mind-independent objects. More specifically, I assume that the disjunctivist advocates naïve realism because they think that this position best articulates how sensory experience seems to us to be just through reflection. If the disjunctivist is correct in this contention, then anyone who accepts the conclusion of the argument from hallucination must also accept that the nature of sensory experience is other than it seems to us to be. In turn, one may complain that any such error theory is liable to lead to sceptical consequences. A Humean scepticism about the senses launches a challenge about our knowledge of the world through questioning the conception we have of what sense experience is, and how it can provide knowledge of the world. (shrink)

John Campbell investigates how consciousness of the world explains our ability to think about the world; how our ability to think about objects we can see depends on our capacity for conscious visual attention to those things. He illuminates classical problems about thought, reference, and experience by looking at the underlying psychological mechanisms on which conscious attention depends.

Hallucination is a big deal in contemporary philosophy of perception. The main reason for this is that the way hallucination is treated marks an important stance in one of the most hotly contested debates in this subdiscipline: the debate between 'relationalists' and 'representationalists'. I argue that if we take hallucinations to be a form of mental imagery, then we have a very straightforward way of arguing against disjunctivism: if hallucination is a form of mental imagery and if mental imagery and (...) perception have some substantive common denominator, then a fortiori, perception and hallucination will also have a substantive common denominator. (shrink)

This book provides the first full-length treatment of disjunctivism about visual experiences in the service of defending a naive realist theory of veridical visual perception. It includes detailed theories of hallucination and illusion that show how such states can be indistinguishable from veridical experiences without sharing any common character.

What are hallucinations? A common view in the philosophical literature is that hallucinations are degenerate kinds of perceptual experience. I argue instead that hallucinations are degenerate kinds of sensory imagination. As well as providing a good account of many actual cases of hallucination, the view that hallucination is a kind of imagination represents a promising account of hallucination from the perspective of a disjunctivist theory of perception like naïve realism. This is because it provides a way of giving a positive (...) characterisation of hallucination—rather than characterising hallucinations in negative, relational, terms as mental events that are subjectively indistinguishable from veridical perceptual experiences. (shrink)

In recent years, a number of philosophers have attempted to fix paradoxes of the counterfactual account of causation by making causation contrastive. In this framework, causation is understood to be not a two-place relationship between a cause and an effect but a three or four-place relationship between a cause, an effect and a contrast on the side of the cause, the effect or both. I argue that contrasting helps resolving certain paradoxes only if an account of admissibility of the chosen (...) set of contrasts is given. I show by means of numerous examples that it is contextual features that determine admissibility. This way, context becomes part of the semantics of causation. I finally argue that once contextualised, explicit contrasting is redundant: causation is therefore a three-place relationship between a cause, an effect and a context. (shrink)

Disjunctivism about sensory experience is frequently put forward in defence of a particular conception of perception and perceptual experience known as naïve realism. In this paper, I present an argument against naïve realism that proceeds through a rejection of disjunctivism. If the naïve realist must also be a disjunctivist about the phenomenal nature of experience, then naïve realism should be abandoned.

Perceptual experiences have been construed either as representational mental states—Representationalism—or as direct mental relations to the external world—Disjunctivism. Both conceptions are critical reactions to the so-called ‘Argument from Hallucination’, according to which perceptions cannot be about the external world, since they are subjectively indiscriminable from other, hallucinatory experiences, which are about sense-data ormind-dependent entities. Representationalism agrees that perceptions and hallucinations share their most specific mental kind, but accounts for hallucinations as misrepresentations of the external world. According to Disjunctivism, the phenomenal (...) character of perceptions is exhausted by worldly objects and features, and thus must be different from the phenomenal character of hallucinations. Disjunctivism claims that subjective indiscriminability is not the result of a common experiential ground, but is because of our inability to discriminate, from the inside, hallucinations from perceptions. At first sight, Representationalism is more congenial to the way cognitive science deals with perception. However, empirically oriented revisions of Disjunctivism could be developed and tested by giving a metacognitive account of hallucinations. Two versions of this account can be formulated, depending on whether metacognition is understood as explicit metarepresentation or as implicit monitoring of first-order informational states. The first version faces serious objections, but the second is more promising, as it embodies a more realistic view of perceptual phenomenology as having both sensory and affective aspects. Affectbased phenomenology is constituted by various metacognitive feelings, such as the feeling of being perceptually confronted with the world itself, rather than with pictures or mere representations. (shrink)

Direct realists think that we can't get a clear view the nature of /hallucinating a white picket fence/: is it /representing a white picket fence/? is it /sensing white-picket-fencily/? is it /being acquainted with a white' picketed' sense-datum/? These are all epistemic possibilities for a single experience; hence they are all metaphysical possibilities for various experiences. Hallucination itself is a disjunctive or "multidisjunctive" category. I rebut MGF Martin's argument from statistical explanation for his "epistemic" conception of hallucination, but his view (...) embeds in my view as a "reference-fixer". (shrink)

Disjunctivism is the focus of a lively debate spanning the philosophy of perception, epistemology, and the philosophy of action. Adrian Haddock and Fiona Macpherson present 17 specially written essays, which examine the different forms of disjunctivism and explore the connections between them.

We investigate the nature of the sense of presence that usually accompanies perceptual experience. We show that the notion of a sense of presence can be interpreted in two ways, corresponding to the sense that we are acquainted with an object, and the sense that the object is real. In this essay, we focus on the sense of reality. Drawing on several case studies such as derealization disorder, Parkinson’s disease and virtual reality, we argue that the sense of reality is (...) two-way independent from the spatial and sensory contents of experience. We suggest that the sense of reality is an affective experience akin to a metacognitive feeling. Finally, we present a potentially important implication of our account for the current debate between Intentionalism and Naïve Realism. Since perception is “opaque” with respect to the reality of what is perceived, Intentionalism cannot refer to the sense of reality as what differentiates perception from sensory-like experiences such as imaginings. In contrast, Naïve Realism has an independent explanation of the specificity of perception. (shrink)

This paper argues that naïve realism has an epistemic advantage over other rival views. The argument consists of two steps. First, I argue that the phenomenology of veridical visual experience plays an indispensable role in explaining how we can refer to the experience as a justificatory reason for a demonstrative judgment. Second, I argue that only naïve realism can coherently allow a veridical visual experience to be used as a factive reason.

This work explains how different theories of causation confront causal overdetermination. Chapters clarify the problem of overdetermination and explore its fundamental aspects. It is argued that a theory of causation can account for our intuitions in overdetermination cases only by accepting that the adequacy of our claims about causation depends on the context in which they are evaluated.The author proposes arguments for causal contextualism and provides insight which is valuable for resolution of the problem. -/- These chapters enable readers to (...) quickly absorb different perspectives on overdetermination and important theories of causation, therefore it is a work that will have a broad appeal. (shrink)

I argue that the possibility of non-perceptual experience need not compel a naïve realist to adopt a disjunctive conception of experience. Instead, they can maintain that the nature of perceptual and hallucinatory experience is the same, while still claiming that perceptual experience is presentational of the objects of perception. On such a view the difference between perceptual and non-perceptual experience will lie in the nature of the objects that are so presented. I will defend a view according to which in (...) non-perceptual experience one is presented with mere universals, while in perceptual experience one is presented with the instantiation of a universal by a particular. This is to adopt disjunctivism about the objects of experience, about that which is apparently present in experience. (shrink)