The Humean view that conceivability entails possibility can be criticized via input from cognitive psychology. A mainstream view here has it that there are two candidate codings for mental representations (one of them being, according to some, reducible to the other): the linguistic and the pictorial, the difference between the two consisting in the degree of arbitrariness of the representation relation. If the conceivability of P at issue for Humeans involves the having of a linguistic mental representation, then it is (...) easy to show that we can conceive the impossible, for impossibilities can be represented by meaningful bits of language. If the conceivability of P amounts to the pictorial imaginability of a situation verifying P, then the question is whether the imagination at issue works purely qualitatively, that is, only by phenomenological resemblance with the imagined scenario. If so, the range of situations imaginable in this way is too limited to have a significant role in modal epistemology. If not, imagination will involve some arbitrary labeling component, which turns out to be sufficient for imagining the impossible. And if the relevant imagination is neither linguistic nor pictorial, Humeans will appear to resort to some representational magic, until they come up with a theory of a ‘third code’ for mental representations. (shrink)

Prior to the twentieth century, theories of knowledge were inherently perceptual. Since then, developments in logic, statis- tics, and programming languages have inspired amodal theories that rest on principles fundamentally different from those underlying perception. In addition, perceptual approaches have become widely viewed as untenable because they are assumed to implement record- ing systems, not conceptual systems. A perceptual theory of knowledge is developed here in the context of current cognitive science and neuroscience. During perceptual experience, association areas in the (...) brain capture bottom-up patterns of activation in sensory-motor areas. Later, in a top-down manner, association areas partially reactivate sensory-motor areas to implement perceptual symbols. The stor- age and reactivation of perceptual symbols operates at the level of perceptual components – not at the level of holistic perceptual expe- riences. Through the use of selective attention, schematic representations of perceptual components are extracted from experience and stored in memory (e.g., individual memories of green, purr, hot). As memories of the same component become organized around a com- mon frame, they implement a simulator that produces limitless simulations of the component (e.g., simulations of purr). Not only do such simulators develop for aspects of sensory experience, they also develop for aspects of proprioception (e.g., lift, run) and introspec- tion (e.g., compare, memory, happy, hungry). Once established, these simulators implement a basic conceptual system that represents types, supports categorization, and produces categorical inferences. These simulators further support productivity, propositions, and ab- stract concepts, thereby implementing a fully functional conceptual system. Productivity results from integrating simulators combinato- rially and recursively to produce complex simulations. Propositions result from binding simulators to perceived individuals to represent type-token relations. Abstract concepts are grounded in complex simulations of combined physical and introspective events. Thus, a per- ceptual theory of knowledge can implement a fully functional conceptual system while avoiding problems associated with amodal sym- bol systems. Implications for cognition, neuroscience, evolution, development, and artificial intelligence are explored. (shrink)

Three thoughts strongly influence recent work on sensory imagination, often without explicit articulation. The image thought says that all mental states involving a mental image are imaginative. The attitude thought says that, if there is a distinctive imaginative attitude, it is a single, monolithic attitude. The function thought says that the functions of sensory imagination are identical or akin to functions of other mental states such as judgment or belief. Taken together, these thoughts create a theoretical context within which eliminativism (...) appears attractive. Eliminativism is the idea that we needn’t refer to a distinctive attitude in order to characterize sensory imagination: the attitudes involved in other states provide all the resources we need. Peter Langland-Hassan’s account of sensory imagination provides an example of such eliminativism. Via close examination of this account, I make manifest the three thoughts and their collective tendency to support eliminativism. I argue that all three are dubious, and that we should reject eliminativism; we need a distinctive imaginative attitude if we are to adequately explicate sensory imagination. (shrink)

We offer an ecological (Gibsonian) alternative to cognitive (im)penetrability. Whereas Pylyshyn explains cognitive (im)penetrability by focusing solely on computations carried out by the nervous system, according to the ecological approach the perceiver as a knowing agent influences the entire animal-environmental system: in the determination of what constitutes the environment (affordances), what constitutes information, what information is detected and, thus, what is perceived.

The transparency of perceptual experience has been invoked in support of many views about perception. I argue that it supports a form of enactivism—the view that capacities for perceptual experience and for intentional agency are essentially interdependent. I clarify the perceptual phenomenon at issue, and argue that enactivists should expect to find a parallel instance of transparency in our agentive experience, and that the two forms of transparency are constitutively interdependent. I then argue that i) we do indeed find such (...) parallels: the way in which an action is directed towards its goal through our bodily movements parallels the way in which an experience is directed towards its object through our perceptual sensation, and ii) reflecting on sensorimotor skills shows why the two instances of transparency are constitutively interdependent. Section 4 gives reasons for generalizing beyond the cases considered so far by applying the enactive view to Kohler's landmark studies of perceptual adaptation. The final section clarifies the form of enactivism to which the previous sections point. The view that emerges is one whereby our perceptual and practical skills are interrelated aspects of a single capacity to have one's mind intentionally directed upon the world. The transparency of experience, on this view, is achieved in virtue of our capacities as agents as much as it is given in virtue of our capacities as perceivers. (shrink)

One standard objection to the view that phenomenal experience is functionally determined is based upon what has come to be called ‘The Absent Qualia Hypothesis’, the idea that there could be a person or a machine that was functionally exactly like us but that felt or consciously experienced nothing at all. Advocates of this hypothesis typically maintain that we can easily imagine possible systems that meet the appropriate functional specifications but that intuitively lack any phenomenal consciousness. Ned Block, for example, (...) asks us to suppose that a billion Chinese people are each given a two-way radio with which to communicate with one another and with an artificial body. The movements of the body are controlled by the radio signals, and the signals themselves are made in accordance with instructions the Chinese people receive from a vast display in the sky which is visible to all of them. The instructions are such that the participating Chinese people together realize whatever programs the functionalist supposes underlie human phenomenal experience. (shrink)

Can theories of mental imagery, conscious mental contents, developed within cognitive science throw light on the obscure (but culturally very significant) concept of imagination? Three extant views of mental imagery are considered: quasi‐pictorial, description, and perceptual activity theories. The first two face serious theoretical and empirical difficulties. The third is (for historically contingent reasons) little known, theoretically underdeveloped, and empirically untried, but has real explanatory potential. It rejects the “traditional” symbolic computational view of mental contents, but is compatible with recentsituated (...) cognition and active visionapproaches in robotics. This theory is developed and elucidated. Three related key aspects of imagination (non‐discursiveness, creativity, and seeing as) raise difficulties for the other theories. Perceptual activity theory presents imagery as non‐discursive and relates it closely to seeing as. It is thus well placed to be the basis for a general theory of imagination and its role in creative thought. (shrink)

: Peter Galison has recently claimed that twentieth-century microphysics has been pursued by two distinct experimental traditions--the image tradition and the logic tradition--that have only recently merged into a hybrid tradition. According to Galison, the two traditions employ fundamentally different forms of experimental argument, with the logic tradition using statistical arguments, while the image tradition strives for non-statistical demonstrations based on compelling ("golden") single events. I show that discoveries in both traditions have employed the same statistical form of argument, even (...) when basing discovery claims on single, golden events. Where Galison sees an epistemic divide between two communities that can only be bridged by a creole- or pidgin-like "interlanguage," there is in fact a shared commitment to a statistical form of experimental argument. (shrink)

The scientific concepts of mental imagery and hallucinations are each used independently of the other; uses that simultaneously evoke and obscure their historical connections. In this paper, I aim to illustrate the relevance of examining one of these historical connections for studying the current uses of these two concepts in neuroimaging experiments. To this end, I will highlight interdependent associations within the histories of each of the concepts that continue to contribute to their independent uses.That mental imagery and hallucinations are (...) used independently of each other is evident in the way that each concept influences investigations in isolation of the other. Within the neurosciences, mental imagery is... (shrink)

In response to widespread doubts among professional philosophers (Russell, Horwich, Dietrich, McGinn, Chalmers), Stoljar argues for a ‘reasonable optimism’ about progress in philosophy. He defends the large and surprising claim that ‘there is progress on all or reasonably many of the big questions.’ However, Stoljar’s caveats and admitted avoidance of historical evidence permits overlooking persistent controversies in philosophy of mind and cognitive science that are essentially unchanged since the 17th Century. Stoljar suggests that his claims are commonplace in philosophy departments (...) and, indeed, the evidence I adduce constitutes an indictment of the widely shared view among professional analytic philosophers. (shrink)

In this paper I evaluate embodied social cognition, embodied cognition’s account of how we understand others. I identify and evaluate three claims that motivate embodied social cognition. These claims are not specific to social cognition; they are general hypotheses about cognition. As such, they may be used in more general arguments for embodied cognition. I argue that we have good reasons to reject these claims. Thus, the case for embodied social cognition fails. Moreover, to the extent that general arguments for (...) embodied cognition rest on these premises, they are correspondingly uncompelling. (shrink)

One of the principal tasks Dennett sets himself in Consciousness Explained is to demolish the Cartesian theater model of phenomenal consciousness, which in its contemporary garb takes the form of Cartesian materialism: the idea that conscious experience is a process of presentation realized in the physical materials of the brain. The now standard response to Dennett is that, in focusing on Cartesian materialism, he attacks an impossibly naive account of consciousness held by no one currently working in cognitive science or (...) the philosophy of mind. Our response is quite different. We believe that, once properly formulated, Cartesian materialism is no straw man. Rather, it is an attractive hypothesis about the relationship between the computational architecture of the brain and phenomenal consciousness, and hence one that is worthy of further exploration. Consequently, our primary aim in this paper is to defend Cartesian materialism from Dennett’s assault. We do this by showing that Dennett’s argument against this position is founded on an implicit assumption (about the relationship between phenomenal experience and information coding in the brain), which while valid in the context of classical cognitive science, is not forced on connectionism. (shrink)

In Sense and Content , Christopher Peacocke points out that two equally-sized trees at different distances from the perceiver are normally represented to be the same size, despite the fact that in a certain sense the nearer tree looks bigger ; he concludes on the basis of this observation that visual experiences possess irreducibly phenomenal properties. This argument has received the most attention of all of Peacocke’s arguments for separatism—the view that the intentional and phenomenal properties of experiences are independent (...) of one another. However, despite its notoriety, the argument is widely misunderstood and underappreciated. I argue that once the structure of the argument is clarified and the replies that have been offered are considered closely, one must conclude that the trees argument is successful. (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.

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. (shrink)

The paper offers a solution to the generality problem for a reliabilist epistemology, by developing an “algorithm and parameters” scheme for type-individuating cognitive processes. Algorithms are detailed procedures for mapping inputs to outputs. Parameters are psychological variables that systematically affect processing. The relevant process type for a given token is given by the complete algorithmic characterization of the token, along with the values of all the causally relevant parameters. The typing that results is far removed from the typings of folk (...) psychology, and from much of the epistemology literature. But it is principled and empirically grounded, and shows good prospects for yielding the desired epistemological verdicts. The paper articulates and elaborates the theory, drawing out some of its consequences. Toward the end, the fleshed-out theory is applied to two important case studies: hallucination and cognitive penetration of perception. (shrink)

Visual imagination (or visualization) is peculiar in being both free, in that what we imagine is up to us, and useful to a wide variety of practical reasoning tasks. How can we rely upon our visualizations in practical reasoning if what we imagine is subject to our whims? The key to answering this puzzle, I argue, is to provide an account of what constrains the sequence in which the representations featured in visualization unfold—an account that is consistent with its freedom. (...) Three different proposals are outlined, building on theories that link visualization to sensorimotor predictive mechanisms (e.g., efference copies, forward models ). Each sees visualization as a kind of reasoning, where its freedom consists in our ability to choose the topic of the reasoning. Of the three options, I argue that the approach many will find most attractive—that visualization is a kind of off-line perception, and is therefore in some sense misrepresentational—should be rejected. The two remaining proposals both conceive of visualization as a form of sensorimotor reasoning that is constitutive of one’s commitments concerning the way certain kinds of visuomotor scenarios unfold. According to the first, these commitments impinge on one’s web of belief from without, in the manner of normal perceptual experience; according to the second, these commitments just are one’s (occurrent) beliefs about such generalizations. I conclude that, despite being initially counterintuitive, the view of visualization as a kind of occurrent belief is the most promising. (shrink)

Provided we agree about the thing, it is needless to dispute about the terms. —David Hume, A treatise of human nature, Book 1, section VIIMap-like representations are frequently invoked as an alternative type of representational vehicle to a language of thought. This view presupposes that map-systems and languages form legitimate natural kinds of cognitive representational systems. I argue that they do not, because the collections of features that might be taken as characteristic of maps or languages do not themselves provide (...) scientifically useful information above and beyond what the individual features provide. To bring this out, I sketch several allegedly distinctive features of maps, and show how they can easily be grafted onto a simple logical language, resulting in a hybrid “manguage.” The ease with which these linguistic and map-like properties can be integrated into a single representational system raises the question of what work broader categories like language and map are doing. I maintain.. (shrink)

Contemporary memory sciences describe processes that are dynamic and constructive. This has led some philosophers to weaken the relationship between memory and epistemology; though remembering can give rise to epistemic success, it is not itself an epistemic success state. I argue that non-epistemic theories will not do; they provide neither necessary nor sufficient conditions for remembering that p. I also argue that the shortcomings of the causal theory are epistemic in nature. Consequently, a theory of remembering must account for both (...) its fundamentally epistemic nature and for its constructive and dynamic processes. (shrink)

I interpret the anti-idealist manoeuverings of the second half of Moore's 'The refutation of idealism', material as widely cited for its discussion of 'transparency' and 'diaphanousness' as it is deeply obscure. The centerpiece of these manoeuverings is a phenomenological argument for a relational view of perceptual phenomenal character, on which, roughly, 'that which makes the sensation of blue a mental fact' is a non-intentional relation of conscious awareness, a view close to the opposite of the most characteristic contemporary view going (...) under the transparency rubric. The discussion of transparency and diaphanousness is a sidelight, its principal purpose to shore up the main line of argumentation against criticism; in those passages all Moore argues is that the relation of conscious awareness is not transparent, while acknowledging that it can seem to be. (shrink)

Both the traditional Aristotelian and modern symbolic approaches to logic have seen logic in terms of discrete symbol processing. Yet there are several kinds of argument whose validity depends on some topological notion of continuous variation, which is not well captured by discrete symbols. Examples include extrapolation and slippery slope arguments, sorites, fuzzy logic, and those involving closeness of possible worlds. It is argued that the natural first attempts to analyze these notions and explain their relation to reasoning fail, so (...) that ignorance of their nature is profound. (shrink)

Mental imagery (varieties of which are sometimes colloquially refered to as “visualizing,” “seeing in the mind's eye,” “hearing in the head,” “imagining the feel of,” etc.) is quasi-perceptual experience; it resembles perceptual experience, but occurs in the absence of the appropriate external stimuli. It is also generally understood to bear intentionality (i.e., mental images are always images of something or other), and thereby to function as a form of mental representation. Traditionally, visual mental imagery, the most discussed variety, was thought (...) to be caused by the presence of picturelike representations (mental images) in the mind, soul, or brain, but this is no longer universally accepted. (shrink)

Twentieth century philosophy and psychology have been peculiarly averse to mental images. Throughout nearly two and a half millennia of philosophical wrangling, from Aristotle to Hume to Bergson, images (perceptual and quasi-perceptual experiences), sometimes under the alias of "ideas", were almost universally considered to be both the prime contents of consciousness, and the vehicles of cognition. The founding fathers of experimental psychology saw no reason to dissent from this view, it was commonsensical, and true to the lived experience of conscious (...) thinking. However, early in this century, just about when the behaviorist revolution in psychology was loudly declaring the scientific illegitimacy of any attempt to study consciousness, and the concomitant non-existence of imagery (Watson, 1913; see Thomas, 1989), philosophy was undergoing its "linguistic turn", a turn to seeing philosophy as essentially about language rather than the world, even the 'inner' world. For decades, the very concept of the mental image was suspect, and it was certainly banished from playing any major role in theories of mind and of thinking. Ralph Ellis' Questioning Consciousness, together with the recent speculations of certain influential neuroscientists (Edelman, 1992; Damasio, 1994), may be signaling the end this unusual era. (shrink)