" Biosemantics " was the title of a paper on mental representation originally printed in The Journal of Philosophy in 1989. It contained a much abbreviated version of the work on mental representation in Language Thought and Other Biological Categories. There I had presented a naturalist theory of intentional signs generally, including linguistic representations, graphs, charts and diagrams, road sign symbols, animal communications, the "chemical signals" that regulate the function of glands, and so forth. But the term " biosemantics " (...) has usually been applied only to the theory of mental representation. Let me first characterize a more general class of theories called "teleological theories of mental content" of which biosemantics is an example. Then I will discuss the details that distinguish biosemantics from other naturalistic teleological theories. (shrink)

Research on human infants has begun to shed light on early-developing processes for segmenting perceptual arrays into objects. Infants appear to perceive objects by analyzing three-dimensional surface arrangements and motions. Their perception does not accord with a general tendency to maximize figural goodness or to attend to nonaccidental geometric relations in visual arrays. Object perception does accord with principles governing the motions of material bodies: Infants divide perceptual arrays into units that move as connected wholes, that move separately from one (...) another, that tend to maintain their size and shape over motion, and that tend to act upon each other only on contact. These findings suggest that o general representation of object unity and boundaries is interposed between representations of surfaces and representations of objects of familiar kinds. The processes that construct this representation may be related to processes of physical reasoning. (shrink)

In this paper I argue for a view of groups, things like teams, committees, clubs and courts. I begin by examining features all groups seem to share. I formulate a list of six features of groups that serve as criteria any adequate theory of groups must capture. Next, I examine four of the most prominent views of groups currently on offer—that groups are non-singular pluralities, fusions, aggregates and sets. I argue that each fails to capture one or more of the (...) criteria. Last, I develop a view of groups as realizations of structures. The view has two components. First, groups are entities with structure. Second, since groups are concreta, they exist only when a group structure is realized. A structure is realized when each of its functionally defined nodes or places are occupied. I show how such a view captures the six criteria for groups, which no other view of groups adequately does, while offering a substantive answer to the question, “What are groups?”. (shrink)

In this paper I argue that causal relations between objects are represented in visual experience, and contrast my argument and its conclusion with Michotte's results from the 1960's.

It’s often held that undetectable inversion of mental qualities is, if not possible, at least conceivable. It’s thought to be conceivable that the mental quality your visual states exhibit when you see something red in standard conditions is literally of the same type as the mental quality my visual states exhibit when I see something green in such circumstances. It’s thought, moreover, to be conceivable that such inversion of mental qualities could be wholly undetectable by any third-person means. And since (...) first- person access is limited to a single individual, and so could not reveal a disparity in mental quality between us, third-person undetectability means undetectability tout court. (shrink)

Object perception deploys a suite of perceptual capacities that constrains attention, guides reidentification, subserves recognition, and anchors demonstrative thought. Objects for perception—perceptual objects—are the targets of such capacities. Characterizing perceptual objects for multisensory perception faces two puzzles. First is the diversity of objects across sensory modalities. Second is the unity of multisensory perceptual objects. This paper resolves the puzzles. Objects for perception are structured mereologically complex individuals. Perceptual objects are items that bear perceptible features and have perceptible parts arranged to (...) form a unified whole. This circumscribes the targets of object perception where neutral talk concerning intentional objects and objects of perception cannot. Nonetheless, it is more permissive than identifying perceptual objects with material bodies, which excludes too much and leans too heavily on vision. The account thus is tailored to capture the role of objects in perception beyond vision: tactual, auditory, and olfactory objects are individuals with differing structures. Its flexibility also enables the account to accommodate shared objects for multisensory perception: multisensory perceptual objects are mereologically complex individuals with hybrid structure. For instance, one can bimodally perceive a common whole with parts accessible to one but not both modalities. Each sense provides a partial perspective on a complex whole that is perceptible through the coordinated use of multiple senses. Understanding perceptual objects as structured mereologically complex individuals thus provides a theoretically useful notion of an object for multisensory perception that resolves the puzzles of diversity and of unity. (shrink)

I argue that there are phenomenological constraints on what it is to see an object, and that these are overlooked by some theories that offer allegedly sufficient causal and counterfactual conditions on object-seeing.

In this paper I propose a model of demonstrative thought. I distinguish token-demonstratives, that pick out individuals, from type-demonstratives, that pick out kinds, or properties, and provide a similar treatment for both. I argue that it follows from my model of demonstrative thought, as well as from independent considerations, that demonstration, as a mental act, operates directly on mental representations, not external objects. That is, though the relation between a demonstrative and the object or property demonstrated is semantically direct, the (...) mechanism by which a demonstrative acquires its referent involves mediation by a perceptual representation. Finally, I argue that so-called 'demonstrative concepts'—which I treat as type-demonstratives—cannot perform the various philosophical functions that have been assigned to them. (shrink)

Four-month-old infants sometimes can perceive the unity of a partly hidden object. In each of a series of experiments, infants were habituated to one object whose top and bottom were visible but whose center was occluded by a nearer object. They were then tested with a fully visible continuous object and with two fully visible object pieces with a gap where the occluder had been. Pattems of dishabituation suggested that infants perceive the boundaries of a partly hidden object by analyzing (...) the movements of its surfaces: infants perceived a connected object when its ends moved in a common translation behind the occluder. Infants do not appear to perceive a connected object by analyzing the colors and forms of surfaces: they did not perceive a connected object when its visible parts were stationary, its color was homogeneous, its edges were aligned, and its shape was simple and regular. These findings do not support the thesis, from gestalt psychology, that object perception first arises as a consequence of a tendency to perceive the simplest, most regular configuration, or the Piagetian thesis that object perception depends on the prior coordination of action. Perception of objects may depend on an inherent conception of what an object is. (shrink)

Much of the philosophical work on perception has focused on vision. Recently, however, philosophers have begun to correct this ‘tunnel vision’ by considering other modalities. Nevertheless, relatively little has been written about the chemical senses—olfaction and gustation. The focus of this paper is olfaction. In light of new physiological and psychophysical research on olfaction, I consider whether olfactory experience is object-based. In particular, I explore the claim that “odor objects” constitute sensory individuals. It isn’t obvious—at least at the outset—whether they (...) meet the widely accepted principles of object individuation and recognition at work in the visual and auditory cases. Among the general issues I consider, then, is whether these traditional principles form necessary, or simply sufficient, conditions on object perception. As we see, at the very least, considering the object-recognition model of olfaction challenges us to look more closely at well-entrenched models of object perception. But the payoff of doing so is high. We not only learn something about a modality that philosophers have historically neglected; by asking new questions and challenging old assumptions, we also further our understanding of perception in general. (shrink)

Many of the objects that we perceive have an important characteristic: When they move, they change shape. For instance, when you watch a person walk across a room, her body constantly deforms. I suggest that we exercise a type of perceptual constancy in response to changes of this sort, which I call structure constancy. In this paper I offer an account of structure constancy. I introduce the notion of compositional structure, and propose that structure constancy involves perceptually representing an object (...) as retaining its compositional structure over time. I argue that compositional structure is represented in visual phenomenology, and I also assemble empirical evidence in support of the claim that compositional structure is recovered by the visual system. Finally, I draw out consequences of this account. I argue that structure constancy has implications for the predictive capacities of perception, and that the phenomenon places important constraints on viable accounts of both the format and reference frame of visual experience. (shrink)

The philosophy of perception has been mostly focused on vision, to the detriment of other modalities like audition or olfaction. In this paper I focus on olfaction and olfactory experience, and raise the following questions: is olfaction a perceptual-representational modality? If so, what does it represent? My goal in the paper is, firstly, to provide an affirmative answer to the first question, and secondly, to argue that olfaction represents odors in the form of olfactory objects, to which olfactory qualities are (...) attributed. In order to do this I develop an empirically adequate notion of olfactory object that is sensitive to the peculiarities of olfaction, and defend it against various objections. (shrink)

This paper defends two theses about sensory objects. The more general thesis is that directly sensed objects are those delivered by sub-personal processes. It is shown how this thesis runs counter to perceptual atomism, the view that wholes are always sensed indirectly, through their parts. The more specific thesis is that while the direct objects of audition are all composed of sounds, these direct objects are not all sounds—here, a composite auditory object is a temporal sequence of sounds (whereas a (...) composite visual object is a spatial composite). Many composite objects are directly heard in the sense just mentioned. There is a great variety of such composite auditory objects—melodies, harmonies, sequences of phonemes, individual voices, meaning-carrying sounds, and so on. This diversity of auditory objects has an important application to aesthetics. Perceivers do not naturally or easily attend simultaneously to auditory objects that overlap in time. Yet, aesthetic appreciation depends on such an allocation of attention to overlapping objects. (shrink)

There is a growing consensus in the philosophical literature that sounds differ rather profoundly from colors. Colors are qualities, while sounds are particulars of some sort or other, such as events or pressure waves. A key motivation for this is that sounds seem to be transient, to evolve over time, to begin and end, while colors seem like stable qualities of objects' surfaces. I argue that sounds are indeed, like colors, stable qualities of objects. Sounds are not transient, and they (...) do not seem to be, even though they are typically perceived transiently. In particular, sounds are dispositions of objects to vibrate in response to being stimulated. This stable property view of sounds aligns nicely with, and owes an inspirational debt to, reflectance physicalist accounts of color. The upshot is a unified picture of colors, sounds, and the perception thereof. (shrink)

Sounds are audible, and sound sources are audible. What is the audible relation between audible sounds and audible sources? Common talk and philosophy suggest three candidates. The first is that sounds audibly are properties instantiated by their sources. I argue that sounds are audible individuals and thus are not audibly instantiated by audible sources. The second is that sounds audibly are effects of their sources. I argue that auditory experience presents no compelling evidence that sounds audibly are causally related to (...) audible sources. The third is that sounds audibly are related mereologically to their sources. I present and offer a defence of this third candidate. (shrink)

Our auditory experience involves the experience of auditory objects—sequences of distinct sounds, or parts of continuous sounds—that are experienced as grouped together into a single sound or “stream” of sounds. In this paper I argue that it is not possible to explain what it is to experience an auditory object as such—i.e. to experience a sequence of sounds as grouped—in purely auditory terms; rather, to experience an auditory object as such is to experience a sequence of sounds as having been (...) (apparently) produced by the same source. (shrink)

Intelligent systems are faced with the problem of securing a principled (ideally, veridical) relationship between the world and its internal representation. I propose a unified approach to visual representation, addressing both the needs of superordinate and basic-level categorization and of identification of specific instances of familiar categories. According to the proposed theory, a shape is represented by its similarity to a number of reference shapes, measured in a high-dimensional space of elementary features. This amounts to embedding the stimulus in a (...) low-dimensional proximal shape space. That space turns out to support representation of distal shape similarities which is veridical in the sense of Shepard's (1968) notion of second-order isomorphism (i.e., correspondence between distal and proximal similarities among shapes, rather than between distal shapes and their proximal representations). Furthermore, a general expression for similarity between two stimuli, based on comparisons to reference shapes, can be used to derive models of perceived similarity ranging from continuous, symmetric, and hierarchical, as in the multidimensional scaling models (Shepard, 1980), to discrete and non-hierarchical, as in the general contrast models (Tversky, 1977; Shepard and Arabie, 1979). (shrink)

It is tempting to hold that perceptual experience amounts to a co-conscious collection of visual, auditory, tactual, gustatory, and olfactory episodes. If so, each aspect of perceptual experience on each occasion is associated with a specific modality. This paper, however, concerns a core variety of multimodal perceptual experience. It argues that there is perceptually apparent intermodal feature binding. I present the case for this claim, explain its consequences for theorizing about perceptual experience, and defend it against objections. I maintain that (...) just as one thing may perceptually appear at once to jointly bear several features associated with the same sense modality, one thing also may perceptually appear at once to jointly bear features associated with different sense modalities. For instance, just as something may visually appear at once to be both red and round, or to have a red part and a green part, something may multimodally perceptually appear at once to be both bright and loud, or to have a red part and a rough part. The main lesson, I argue, is that perceiving is not just co-consciously seeing, hearing, feeling, tasting, and smelling at the same time. And perceptual phenomenal character is not on each occasion exhausted by that which is distinctive to or associated with a given modality, along with that which accrues thanks to simple co-consciousness. Not all ways of perceiving are modality specific. I defend this account against three main objections: that singular content theorists avoid my conclusions; that apparent infusion of perceptible features is required for perceptually apparent binding but does not occur intermodally; and that the diversity of objects across modalities makes perceptually apparent intermodal binding rare. (shrink)

Forthcoming publication in Auditory Perception and Sounds.

Many authors have posited an “object file” system, which underlies perceptual selection and tracking of objects. Several have proposed that this system internalizes principles specifying what counts as an object and relies on them during tracking. Here I consider a popular view on which the object file system is tuned to entities that satisfy principles of three-dimensionality, cohesion, and boundedness. I argue that the evidence gathered in support of this view is consistent with a more permissive view on which object (...) files select and track according to well-known perceptual organization criteria. Further evidence supplies positive support for the permissive view. (shrink)

Psychophysics and neuroscience demonstrate that different sensory systems interact and influence each other. Perceiving involves extensive cooperation and coordination among systems associated with sight, hearing, touch, smell, and taste. Nonetheless, it remains unclear in what respects conscious perceptual awareness is multisensory. This paper distinguishes six differing varieties of multisensory awareness, explicates their consequences, and thereby elucidates the multisensory nature of perception. It argues on these grounds that perceptual awareness need not be exhausted by that which is associated with each of (...) the respective sensory modalities along with whatever accrues thanks to simple co-consciousness. (shrink)

In this book, Eli Hirsch focuses on identity through time, first with respect to ordinary bodies, then underlying matter, and eventually persons. These are linked at various points with other aspects of identity, such as the spatial unity of things, the unity of kinds, and the unity of groups. He investigates how our identity concept ordinarily operates in these respects. He also asks why this concept is so cental to our thinking and whether we can justify seeing the world in (...) terms of such a concept. This is the revised and updated edition of a hardback published in 1982. (shrink)

We provide some meta-theoretical constraints for the evaluation of a-spatial theories of sounds and auditory perception. We point out some forms of spatial content auditory experience can have. If auditory experience does not necessarily have a rich egocentric spatial content, it must have some spatial content for the relevant mode of perception to be recognizably auditory. An auditory experience devoid of any spatial content, if the notion makes sense at all, would be very different from the auditory experiences we actually (...) enjoy. This is enough to dismiss current a-spatial theories of auditory perception. As a consequence, our initial taxonomy of proximal, medial, and distal theories, as well as our phenomenological argument in favor of distal theories, are still topical. (shrink)

We examine a number of investigations of perceptual economy or, more specifically, of minimum tendencies and minimum principles in the visual perception of form, depth, and motion. A minimum tendency is a psychophysical finding that perception tends toward simplicity, as measured in accordance with a specified metric. A minimum principle is a theoretical construct imputed to the visual system to explain minimum tendencies. After examining a number of studies of perceptual economy, we embark on a systematic analysis of this notion. (...) We examine the notion that simple perceptual representations must be defined within the "geometric constraints" provided by proximal stimulation. We then take up metrics of simplicity. Any study of perceptual economy must use a metric of simplicity; the choice of metric may be seen as a matter of convention, or it may have deep theoretical and empirical implications. We evaluate several answers to the question of why the visual system might favor economical representations. Finally, we examine several accounts of the process for achieving perceptual economy, concluding that those which favor massively parallel processing are the most plausible. (shrink)

Is there a space of the sensory modalities? Such a space would be one in which we can represent all the actual, and at least some of the possible, sensory modalities. The relative position of the senses in this space would indicate how similar and how different the senses were from each other. The construction of such a space might reveal unconsidered features of the actual and possible senses, help us to define what a sense is, and provide grounds that (...) we might use to decide what is one token sense rather than multiple token senses. -/- In this paper, I explore, refine, and defend the idea that we can construct such a space—an idea that I briefly proposed in earlier work (Macpherson 2011a and 2011b). In doing so, I defend the idea from an objection that Richard Gray (2012) has voiced. Gray claims that the dimensions of the space of sensory modalities must generate a non-­‐arbitrary ordering of the senses. He argues that we cannot find dimensions that do so. I disagree. I identify different ways in which a space could be arbitrary but I argue that we can define a space of the sensory modalities in a non-arbitrary manner. I give examples of what the dimensions might be. (shrink)