Fiona Macpherson

In this paper, we present new cases of illusion and hallucination that have not heretofore been identified. We argue that such cases show that the traditional accounts of illusion and hallucination are incorrect because they do not identify all of the cases of non-veridical experience that they need to and they elide important differences between cases. In light of this, we present new and exhaustive definitions of illusion and hallucination. First, we explicate the traditional accounts of illusion and hallucination. We then proceed to outline cases of pure property experience—that is, experience as of properties, but not as of objects. We suggest that some might find it to be plausible that olfactory experience is of this kind. We argue that, within instances of such pure property experience, one can identify cases of veridical property perception, illusory property perception and hallucinatory property experience. With these distinctions in hand, we re-examine ordinary cases of experiences as of objects having properties. Drawing on the ideas uncovered by considering pure property experience, we bring to light many new cases of illusion and hallucination within ordinary experience as of objects having properties. These consist in different combinations of veridical perception, illusory perception and hallucination of both objects and properties. In order to accept that these new cases of illusion and hallucination exist in ordinary experience as of objects having properties, nothing turns on accepting the idea that there is pure property experience, or that olfactory experience is an instance of it. Such a conception of experience is simply a tool—a ladder to gain a good vantage point from which one can appreciate that there are these further cases. But this is a ladder that, as Wittgenstein might say, can be thrown away once it is used. Identifying new instances of illusion and hallucination provides much needed, important data for testing theories of experience and perception—theories that are frequently motivated, and should be judged, by their ability to account for cases of illusion and hallucination.

If beliefs and desires affect perception—at least in certain specified ways—then cognitive penetration occurs. Whether it occurs is a matter of controversy. Recently, some proponents of the predictive coding account of perception have claimed that the account entails that cognitive penetrations occurs. I argue that the relationship between the predictive coding account and cognitive penetration is dependent on both the specific form of the predictive coding account and the specific form of cognitive penetration. In so doing, I spell out different forms of each and the relationship that holds between them. Thus, mere acceptance of the predictive coding approach to perception does not determine whether one should think that cognitive penetration exists. Moreover, given that there are such different conceptions of both predictive coding and cognitive penetration, researchers should cease talking of either without making clear which form they refer to, if they aspire to make true generalisations.

Some naturalistic theories of consciousness give an essential role to teleology.1 This teleology is said to arise due to natural selection. Thus it is claimed that only certain states, namely, those that have been selected for by evolutionary pro- cesses because they contribute to (or once contributed to) an organism’s fitness, are conscious states. These theories look as if they are assigning a creative role to natural selection. If a state is conscious only if it has been selected for, then selec- tion appears to be able to create a new feature of states, namely, their conscious nature. Yet, intuitively, natural selection cannot create anything. Natural selec- tion chooses certain features that already exist and makes them more (or less) prevalent in a population, but it cannot bring features into existence itself. Natu- ral selection can select for conscious states, but it cannot create them. This con- clusion has recently been argued for by Steven Horst (1999). If it is right, then teleological theories of conscious states should be rejected. A state cannot become a conscious experience in virtue of having been selected for by evolu- tionary process

Philosophers and scientists have studied sensory perception and, in particular, vision for many years. Increasingly, however, they have become interested in the nonvisual senses in greater detail and the problem of individuating the senses in a more general way. The Aristotelian view is that there are only five external senses—smell, taste, hearing, touch, and vision. This has, by many counts, been extended to include internal senses, such as balance, proprioception, and kinesthesis; pain; and potentially other human and nonhuman senses. This “multisensory turn” has been driven partly by developments in contemporary psychology and neuroscience, which have revealed a host of complex interrelations and interactions between sensory modalities previously thought to be distinct. Contrasts between modalities and other crossmodal phenomena, including multisensory integration, synesthesia, and sensory substitution, have also begun to receive more attention in a burgeoning scientific and philosophical literature on multisensory perception and other crossmodal effects. This article focuses on recent empirically informed contributions to the philosophy of perception, as well as key scientific works that provide important background information and insights into the nature of the senses and sensory perception. Indeed, one of the lessons of the multisensory turn, and of contemporary philosophy of mind more generally, is that philosophers ignore this body of empirical research at their peril because many human and animal senses turn out to be richer and more complex than philosophers and scientists had previously imagined, making this a fruitful area for interdisciplinary interaction and research.

Unlike those with type 1 blindsight, people who have type 2 blindsight have some sort of consciousness of the stimuli in their blind field. What is the nature of that consciousness? Is it visual experience? I address these questions by considering whether we can establish the existence of any structural—necessary—features of visual experience. I argue that it is very difficult to establish the existence of any such features. In particular, I investigate whether it is possible to visually, or more generally perceptually, experience form or movement at a distance from our body, without experiencing colour. The traditional answer, advocated by Aristotle, and some other philosophers, up to and including the present day, is that it is not and hence colour is a structural feature of visual experience. I argue that there is no good reason to think that this is impossible, and provide evidence from four cases—sensory substitution, achomatopsia, phantom contours and amodal completion—in favour of the idea that it is possible. If it is possible then one important reason for rejecting the idea that people with type 2 blindsight do not have visual experiences is undermined. I suggest further experiments that could be done to help settle the matter.

Is the sense-data theory, otherwise known as indirect realism, a form of representationalism? This question has been underexplored in the extant literature, and to the extent that there is discussion, contemporary authors disagree. There are many different variants of representationalism, and differences between these variants that some people have taken to be inconsequential turn out to be key factors in whether the sense-data theory is a form of representationalism. Chief among these are whether a representationalist takes the phenomenal character of an experience to be explicable in virtue of the properties of an experience that represent something or explicable in virtue of that which gets represented. Another is whether representationalists hold a non-reductionist, or naturalistically or non-naturalistically reductionist variant of representationalism. In addition, subtle differences in what one takes phenomenal character to be on the sense-data theory – either awareness of sense-data or the sense-data themselves – together with one's account of representation, are crucial factors in determining whether sense-data theory is compatible with representationalism. This paper explores these relationships and makes manifest the complexities of the metaphysics of two central theories of perception

From David Hume's famous puzzle about 'the missing shade of blue' to current research into the science of colour, the topic of colour is an incredibly fertile region of study and debate, cutting across philosophy of mind, epistemology, metaphysics and aesthetics as well as psychology. Debates about the nature of our experience of colour and the nature of colour itself are central to contemporary discussion and argument in philosophy of mind and psychology, and philosophy of perception. This outstanding Handbook contains twenty-nine specially commissioned contributions by leading philosophers and examines the most important aspects of philosophy of colour. It is organised into six parts: The Importance of Colour to Philosophy The Science and Spaces of Colour Colour Phenomena Colour Ontology Colour Experience and Epistemology Language, Categories and Thought. The Routledge Handbook of Philosophy of Colour is essential reading for students and researchers in philosophy of mind and psychology, epistemology, metaphysics and aesthetics, as well as for those interested in conceptual issues in the psychology of colour.

Forthcoming (2011) in K. Hawley and F. Macpherson (eds.) The Admissible Contents of Experience, Wiley‐Blackwell. The Admissible Contents of Experience Fiona Macpherson This essay provides an overview of the debate concerning the admissible contents of experience, together with an introduction to the papers in this volume. The debate is one that takes place among advocates of a certain way of thinking of perceptual experiences: that they are states that represent the world. For to say that a state has content is to say that it represents; and its content is usually taken to be that which is represented. One should not be tempted to think that the debate is therefore marginal or esoteric, for this view of perceptual experience has been by far the dominant view of perceptual experience in recent years in philosophy (and in psychology and neuroscience). The debate is about what answer to give to a fundamental question about the nature of perceptual experience, namely: what objects and properties can it represent?

Abstract: This paper seeks to establish whether the cognitive penetration of experience is compatible with experience having nonconceptual content. Cognitive penetration occurs when one’s beliefs or desires affect one’s perceptual experience in a particular way. I examine two different models of cognitive penetration and four different accounts of the distinction between conceptual and nonconceptual content. I argue that one model of cognitive penetration—“classic” cognitive penetration—is compatible with only one of the accounts of nonconceptual content that I identify. I then consider the other model of cognitive penetration—cognitive penetration “lite”. I provide reasons to think that this is compatible with three accounts of nonconceptual content. Moreover, I argue that the account of nonconceptual content that it is not compatible with is a spurious notion of nonconceptual content that ought to be abandoned. Thus, I claim that cognitive penetration lite is compatible with all reasonable specifications of nonconceptual content.

The past 25 years have seen a rapid growth of knowledge about brain mechanisms involved in visual mental imagery. These advances have largely been made independently of the long history of philosophical – and even psychological – reckoning with imagery and its parent concept ‘imagination’. We suggest that the view from these empirical findings can be widened by an appreciation of imagination’s intellectual history, and we seek to show how that history both created the conditions for – and presents challenges to – the scientific endeavor. We focus on the neuroscientific literature’s most commonly used task – imagining a concrete object – and, after sketching what is known of the neurobiological mechanisms involved, we examine the same basic act of imagining from the perspective of several key positions in the history of philosophy and psychology. We present positions that, firstly, contextualize and inform the neuroscientific account, and secondly, pose conceptual and methodological challenges to the scientific analysis of imagery. We conclude by reflecting on the intellectual history of visualization in the light of contemporary science, and the extent to which such science may resolve long-standing theoretical debates.

This chapter explores the evidence for the existence of such new colour experiences and what their philosophical ramifications would be. I first define the notion of ‘novel colours’ and discuss why I think that this is the best name for such colours, rather than the numerous other names that they have sometimes been given in the literature. I then introduce the evidence and arguments for thinking that experiences as of novel colours exist, along with objections that people have had to that evidence and to those arguments. To do so, I outline some facts about ordinary, non-novel colours before considering whether experiences as of novel colours, exist. Then I discuss the potentially significant ramifications the existence of novel colour experiences would have for theories of the metaphysics of colour, theories of the nature of colour experience, and for theories of the nature of perception more generally.

Is the sense‐data theory, otherwise known as indirect realism, a form of representationalism? This question has been under‐explored in the extant literature, and to the extent that there is discussion, contemporary authors disagree. There are many different variants of representationalism, and differences between these variants that some people have taken to be inconsequential turn out to be key factors in whether the sense‐data theory is a form of representationalism. Chief among these are whether a representationalist takes the phenomenal character of an experience to be explicable in virtue of the properties of an experience that represent something or explicable in virtue of that which gets represented. Another is whether representationalists hold a non‐reductionist, or naturalistically or non‐naturalistically reductionist variant of representationalism. In addition, subtle differences in what one takes phenomenal character to be on the sense‐data theory – either awareness of sense‐data or the sense‐data themselves – together with one's account of representation, are crucial factors in determining whether sense‐data theory is compatible with representationalism. This paper explores these relationships and makes manifest the complexities of the metaphysics of two central theories of perception. 1 Many thanks are due to Clare Batty, Derek Brown, and James Stazicker for discussion and feedback on earlier drafts, which made this essay better than it would otherwise have been. This work was supported by two grants from the Arts and Humanities Research Council (grant numbers AH/1027509/1 and AH/L007053/1).