Keith A. Wilson

In the introduction to the Phenomenology of Perception, Merleau-Ponty states that ‘Attention, [...] as a general and formal activity, does not exist’. This paper examines the meaning and truth of this difficult and surprising statement, along with its implications for the account of perception given by theorists such as Dretske and Peacocke. In order to elucidate Merleau-Ponty’s phenomenological account of human perception, I will present two alternative models1 of how attention might be thought to operate. The first is derived from the works of the aforementioned theorists and is, I argue, based upon a largely inaccurate computational or mechanistic understanding of the mind. The second is drawn from the works of Merleau-Ponty and cognitive scientist and philosopher, Alva Noë, and takes into account recent neurological theories concerning the role of attention in human consciousness. On the basis of these models I will argue that attention is an essential, rather than incidental, characteristic of consciousness that is constitutive of both thought and perception, and which cannot be understood in terms of the independent faculty or ‘general and unconditioned power’ that Dretske et al’s account requires. I will conclude by considering two potential counterexamples to my argument, and evaluating the threat that these pose to the phenomenological model.

Visual experience is often characterised as being essentially spatial, and auditory experience essentially temporal. But this contrast, which is based upon the temporal structure of the objects of sensory experience rather than the experiences to which they give rise, is somewhat superficial. By carefully examining the various sources of temporal variation in the chemical senses we can more clearly identify the temporal profile of the resulting smell and taste (aka flavour) experiences. This in turn suggests that at least some of the objects of olfactory experience have significant temporal structure, including interactions between odorants and the body’s own sensory systems. This can help to inform our understanding not only of the metaphysics of olfaction, but the temporal structure of sensory processing and experience in other sense-modalities, including vision and audition.

Visual perception is widely taken to present properties such as redness, roundness, and so on. This in turn might be thought to give rise to accuracy conditions for experience, and so content, regardless of which metaphysical view of perception one endorses. An influential version of this argument—Susanna Siegel’s ’Argument from Appearing’—aims to establish the existence of content as common ground between representational and relational views of perception. This goes against proponents of ‘austere’ relationalism who deny that content plays a substantive role in philosophical explanations of conscious perceptual experience. Though Siegel’s argument purports to be neutral with respect to the metaphysics of perception, it relies upon an equivocation between the presentation of property-types and property-instances. Consequently, the argument begs the question against the austere relational view, and so fails to establish the desired conclusion. So while relationalists can and should allow that experiences have accuracy conditions, it does not follow from this that they have contents of any philosophically interesting or significant kind.

It is widely accepted that there is a visual field, but the analogous notion of an auditory field is rejected by many philosophers on the grounds that the metaphysics or phenomenology of audition lack the necessary spatial or phenomenological structure. In this paper, I argue that many of the common objections to the existence of an auditory field are misguided and that, contrary to a tradition of philosophical scepticism about the spatiality of auditory experience, it is as richly spatial as visual experience—and in some ways even more so. By carefully considering the spatiality and boundedness of audition, along with how sounds or their sources are experienced as occurring within the surrounding acoustic environment, we can gain a better understanding of (i) our auditory experience of space and (ii) the conditions for the existence of spatial sensory fields in general in a way that does not privilege vision over the other senses.

The idea that there are five senses dates back to Aristotle, who was one of the first philosophers to examine them systematically. Though it has become conventional wisdom, many scientists and philosophers would argue that this idea is outdated and inaccurate. Indeed, they have given many different answers to this question, ranging from just three (the number of different kinds of physical energy we can detect) to 33 or more senses. Perhaps surprisingly, the issue remains controversial, partly because it is not clear exactly what should count as a ‘sense’. Should proprioception, balance and kinaesthesis, amongst others, be considered additional senses? And if so, how do we figure out how many senses we really have? (Published in Turkish under the title ‘Çok Duyumlu Algi’)

Each of our sensory modalities—vision, touch, taste, etc.—works on a slightly different timescale, with differing temporal resolutions and processing lag. This raises the question of how, or indeed whether, these sensory streams are co-ordinated or ‘bound’ into a coherent multisensory experience of the perceptual ‘now’. In this paper I evaluate one account of how temporal binding is achieved: the temporal windows hypothesis, concluding that, in its simplest form, this hypothesis is inadequate to capture a variety of multisensory phenomena. Rather, the evidence suggests the existence of a more complex temporal structure in which multiple overlapping windows support distinct functional mechanisms. To aid in the precise formulation of such views, I propose a taxonomy of temporal window types and their characteristics that in turn suggests promising avenues for future empirical and philosophical research. I conclude by examining some philosophical implications of multi-window models for the metaphysics of perception and perceptual experience more generally.

The dual role of olfaction in both smelling and tasting, i.e. flavour perception, makes it an important test case for philosophical theories of sensory individuation. Indeed, the psychologist Paul Rozin claimed that olfaction is a “dual sense”, leading some scientists and philosophers to propose that we have not one, but two senses of smell: orthonasal and retronasal olfaction. In this paper I consider how best to understand Rozin’s claim, and upon what grounds one might judge there to be one or two distinct olfactory modalities. I conclude that while Rozin may be right that humans have dual occurrences of an olfactory ‘sense’, the concept of a sense-modality, and hence the ‘sense’ of smell, is ambiguous between two different notions: a physiological sensory channel and an experiential modality, along the lines suggested by J. J. Gibson. Furthermore, recognising that these are complementary rather than competing conceptions of a sense-modality enables the formulation of a powerful ‘dual-concept’ framework for posing and addressing questions concerning the complex architecture of human multisensory experience.

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.

Charles Travis’s new collection on perception brings together eleven of his previously published essays on this topic, some of which are substantially revised, plus one new essay. The intentionally ambiguous subtitle hints at the author’s endorsement of Fregean anti-psychologism, though influences from Wittgenstein and Austin are equally apparent. The work centres around two major questions in the philosophy of mind and perception. First, Travis argues against the view that perceptual experience, as distinct from perceptual judgement or belief, is representational, and so belongs to what Travis calls ‘the conceptual’. This is contrasted with the ‘non-conceptual’, or ‘historical’; that is, environmental particulars which lack the generality of representational thought. The second is what Travis calls ‘the fundamental question of perception’; namely, how can perceptual experience make the world bear (rationally) upon what we are to think and do? The answer, he argues, cannot be found in terms of relations between thoughts—a purely conceptual affair—but in the way that thought is itself grounded in the particularity of experience. For perceptual experience to bear rationally upon thought at all—or, in more familiar Fregean terms, to bring ‘objects’ under ‘concepts’—perception must first make environmental particulars available to cognition. Thus, Travis argues, experience cannot itself be ‘conceptual’, or representational, on pain of undermining the very thing that grants us a recognisable, and so thinkable, world at all

Many philosophers and scientists take perceptual experience, whatever else it involves, to be representational. In ‘The Silence of the Senses’, Charles Travis argues that this view involves a kind of category mistake, and consequently, that perceptual experience is not a representational or intentional phenomenon. The details of Travis’s argument, however, have been widely misinterpreted by his representationalist opponents, many of whom dismiss it out of hand. This chapter offers an interpretation of Travis’s argument from looks that it is argued presents a genuine and important challenge to orthodox representational views of experience. Whilst this challenge may not be insurmountable, it places a substantial burden upon the representationalist to explain not only how experiences come to have the contents that they do, but how those contents come to feature in our conscious mental lives.

Many philosophers have held that perceptual experience is fundamentally a matter of perceivers being in particular representational states. Such states are said to have representational content, i.e. accuracy or veridicality conditions, capturing the way that things, according to that experience, appear to be. In this thesis I argue that the case against representationalism — the view that perceptual experience is fundamentally and irreducibly representational — that is set out in Charles Travis’s ‘The Silence of the Senses’ (2004) constitutes a powerful, but much misunderstood and neglected argument against this prevailing philosophical orthodoxy. In chapter 2, I present an interpretation of Travis’s arguments that poses a dilemma for the representationalist concerning the indeterminacy and availability of perceptual content. Chapters 3 and 4 evaluate a variety of arguments in favour of such content based upon the nature of appearances, or ‘looks’, including those by Byrne (2009), Siegel (2010) and Schellenberg (2011b), each of which I find to be problematic. Finally, chapters 5 and 6 examine the relationship between representational content and phenomenal character, i.e. what perceptual experience is subjectively like, outlining some potential responses to Travis’s anti-representationalism. These include the external individuation of content and self-knowledge, and the operation of perceptual discriminatory capacities (the latter of which does not necessarily favour a representationalist account of experience). I conclude that Travis’s arguments establish substantive constraints upon the nature and role of perceptual content. Moreover, I argue that the debate centres less upon the existence of such content than its explanatory role, particularly in relation to phenomenal character and the contents of other mental states: belief, intention, thought, knowledge, and so on. This in turn highlights the need for representationalists to better clarify the role of the contents their theories posit, and why such theories constitute a better explanation of the relevant phenomena than the corresponding non-representational view.

Taken at face value, the picture of reality suggested by modern science seems radically opposed to the world as we perceive it through our senses. Indeed, it is not uncommon to hear scientists and others claim that much of our perceptual experience is a kind of pervasive illusion rather than a faithful presentation of various aspects of reality. On this view, familiar properties such as colours and solidity, to take just two examples, do not belong to external objects, but are fictions generated by the brain that we mistakenly ascribe to the world around us. Contrary to this view, I argue that properties like colour and solidity are as much a part of the fabric of reality as gravity and electrons, and that our scientific and common-sense world views are not as opposed to one another as it might first appear.

In his account of visual perception, Thomas Reid describes visible figure as both ‘real and external’ to the eye and as the ‘immediate object of sight’. These claims appear to conflict with Reid's direct realism, since if the ‘immediate’ object of vision is also its direct object, then sight would be perceptually indirect due to the role of visible figure as a perceptual intermediary. I argue that this apparent threat to Reid's direct realism may be resolved by understanding visible figure as the set of geometrical properties that holds between an object's visible surfaces and some particular perspective or point of view. On this relational interpretation of visible figure, and once an ambiguity over the use of the term ‘object’ is resolved, Reid's account of vision is both epistemically and perceptually direct, as well as consistent with his account of the other senses and doctrine of signs.