It is a characteristic feature of our mental make-up that the same perceptual input situation can simultaneously elicit conflicting mental perspectives. This ability pervades our perceptual and cognitive domains. Striking examples are the dual character of pictures in picture perception, pretend play, or the ability to employ metaphors and allegories. I argue that traditional approaches, beyond being inadequate on principle grounds, are theoretically ill equipped to deal with these achievements. I then outline a theoretical perspective that has emerged (...) from a theoretical convergence of perceptual psychology, ethology, linguistics, and developmental research. On the basis of this framework, I argue that corresponding achievements are brought forth by a specific type of functional architecture whose core features are as follows: (1) a perceptualsystem that is biologically furnished with a rich system of conceptual forms, (2) a triggering relation between the sensory input and conceptual forms by which the same sensory input can be exploited by different types or systems of conceptual forms, and (3) computational principles for handling semantically underspecified conceptual forms. Characteristic features of the proposed theoretical framework are pointed out using the Heider–Simmel phenomenon as an example. (shrink)
According to Pylyshyn, the early visual system is able to categorize perceptual inputs into shape classes based on visual similarity criteria; it is also suggested that written words may be categorized within early vision. This speculation is contradicted by the fact that visually unrelated exemplars of a given letter (e.g., a/A) or word (e.g., read/READ) map onto common visual categories.
The Gestalt Bubble model describes a subjective phenomenal experience (what is seen) without taking into account the extraphenomenal constraints of perceptual experience (why it is seen as it is). If it intends to be an explanatory model, then it has to include either stimulus or neural constraints, or both.
In this paper I argue that one of the functions of the perceptualsystem is to detect other people’s emotions when they are expressed in the face. I support this view by developing two separate but interdependent accounts. The first says that facial expressions of emotions carry information about the emotions that produced them, and about some of their properties. The second says that the visual system functions to extract the information that expressions carry about emotions.
The book I review, _Sleights of Mind_, aims to illuminate properties of perceptual systems by discussing human susceptibility to magical illusions. I describe how the authors use psychological principles to explain two tricks, spoon bending and the Miser's Dream. I also argue that the book is congenial to the following view of illusions: susceptibility to illusion is the result of evolutionary trade-offs; perceptual systems must make assumptions in order to function at all, but susceptibility to illusion is the (...) byproduct of such assumptions. (shrink)
What do we see when we look at someone's expression of fear? I argue that one of the things that we see is fear itself. I support this view by developing a theory of affect perception. The theory involves two claims. One is that expressions are patterns of facial changes that carry information about affects. The other is that the visual system extracts and processes such information. In particular, I argue that the visual system functions to detect the (...) affects of others when they are expressed in the face. I develop my theory by drawing on empirical data from psychology and brain science. Finally, I outline a theory of the semantics of affect perception. (shrink)
In his target article, Barsalou cites current work on emotion theory but does not explore its relevance for this project. The connection is worth pursuing, since there is a plausible case to be made that emotions form a distinct symbolic information processing system of their own. On some views, that system is argued to be perceptual: a direct connection with Barsalou's perceptual symbol systems theory. Also relevant is the hypothesis that there may be different modular subsystems (...) within emotion and the perennial tension between cognitive and perceptual theories of emotion. (shrink)
Commentary on "On Specification and the Senses," by Thomas A. Stoffregen and Benoît G. Bardy: Behavioral and Brain Sciences, 24, 195-261 (2001). The target article's value lies not in its defence of specification, or the "global array" concept, but in its challenge to the paradigm of 5+ senses, and its examples of multiple receptor types cooperatively participating in specific information pick-up tasks. Rather than analysing our perceptual endowment into 5+ senses, it is more revealing to type perceptual systems according (...) to task. (shrink)
Philosophers of mind, both in the conceptual analysis tradition and in the empirical informed school, have been implicitly neglecting the potential conceptual role of the Peripheral Nervous System (PNS) in understanding sensory and perceptual states. Instead, the philosophical as well as the neuroscientific literature has been assuming that it is the Central Nervous System (CNS) alone, and more exactly the brain, that should prima facie be taken as conceptually and empirically crucial for a philosophical analysis of such (...) states This is the first monograph that focuses on the PNS and its constitutive role in sensory states, including pain, mechanoception, proprioception, tactile perception, and so forth. -/- The author argues that the brain-centeredness of current philosophy of mind is a prejudice, and proposes a series of original ways in which classic puzzles in the philosophy of mind can be solved once the hypothesis that PNS is a constitutive element of mental states is taken seriously. The author calls this “the Peripheral Mind Hypothesis”, and employs it in a vast range of issues, such as functionalism, physicalism, mental content, embodiment, as well as some issues in neuroethics. -/- Making equal use of conceptual analysis, empirical data from neuroscience, first-person phenomenological data, and philosophical speculation, this work offers a fresh look at, and novel solutions to many philosophical problems. (shrink)
Although Barsalou is right in identifying the importance of perceptual symbols as a means of carrying certain kinds of content, he is wrong in playing down the inferential resources available to amodal symbols. I argue that the case for perceptual symbol systems amounts to a false dichotomy and that it is feasible to help oneself to both kinds of content as extreme ends on a content continuum. The continuum thesis I advance argues for the inferential content at one (...) end and perceptual content at the other. In between the extremes, symbols might have aspects that are either perceptual or propositional-linguistic in character. I argue that this way of characterising the issue preserves the good sense of Barsalou's recognition of perceptual representations and yet avoids the tendency to minimise the gains won with symbolic representations vital to contemporary cognitive science. (shrink)
A metaphor can often create novel features in an object or a situation. This phenomenon has been particularly hard to account for using amodal symbol systems: although highlighting and downplaying can explain the shift of focus, it cannot explain how entirely new features can come about. We suggest here that the dynamism of perceptual symbol systems, particularly the notion of simulator, provides an elegant account of the creativity of metaphor. The elegance lies in the idea that the creation of (...) new features by a metaphor proceeds in the same way as the creation of regular features in a perceptual symbol. (shrink)
This paper deals with the philosophical questions which gave rise to the traditional realist theories of universals. The main thesis is that these same questions may also be interpreted as scientific-empirical questions. The study of these problems has begun only very recently and the relevance of the results for the traditional problem of intensional entities has only been remarked by few workers aware of the philosophical problem. The approach adopted here is that of regarding man as a perceptual (...) class='Hi'>system situated in an environment and showing certain capacities like perception of universals. The possible ways of access to these entities is discussed on the basis of some recent empirical findings related to perception. One conclusion is that in order to answer the basic philosophical question of how properties, particulars and propositions are perceived may be answered within the domains of science, accepting only the usual presuppositions used in it. Basically, such an approach sees the root of the problem in the great complexity of information processing involved in the actual perception of properties, particulars and propositions. (shrink)
Barsalou's theory of perceptual symbol systems is considered from a metacognitive perspective. Two examples are discussed in terms of the proposed perceptual symbol theory. First, recent results in research on feeling-of-knowing judgement are used to argue for a representation of familiarity with input cues. This representation should support implicit memory. Second, the ability of maintaining a theory of other people's beliefs (theory of mind) is considered and it is suggested that a purely simulation-based view is insufficient to explain (...) the available evidence. Both examples characterize areas where Barsalou's theory would benefit from additional detail. (shrink)
It is very tempting to try to reconcile perception and cognition perceptual symbol systems may be a good way to achieve this; but is there actually a perception-cognition continuum? We offer several arguments for and against the existence of such a continuum and in favor of the choice of perceptual symbol systems. One of these arguments is purely theoretical, some are based on PET-scan observations and others are based on research with handicapped subjects who have communication problems associated (...) with cerebral lesions. These arguments suggest that modal perceptual symbols do indeed exist and that perception and cognition might have a common neuronal basis; but perceptual and cognitive activities require the activation of different neuronal structures. (shrink)
Germany's leading contemporary social theorist provides a definitive analysis of art as a social and perceptualsystem which not only represents an important intellectual step in discussions of art but also an important advance in systems theory. Luhmann insists on the radical incommensurability between psychic systems (perception) and social systems (communication). Art is a special kind of communication that operates at the boundary between the social system and consciousness in ways that profoundly irritate communication while remaining strictly (...) internal to the social. Each chapter elaborates a particular aspect of the general problem of art's status as a social system. The book draws on a vast body of research in the social sciences, phenomenology, evolutionary biology, cybernetics, and information theory, combined with an intimate knowledge of art history, literature, aesthetics, and contemporary literary theory. The book also engages virtually every major theorist of art and aesthetics from Baumgarten to Derrida. (shrink)
Journal of Mind and Behavior 28 no. 2 (2007), pp. 135-156. The self-prompting theory of consciousness holds that conscious perceptual experience occurs when non-routine perceptual data prompt the activation of a plan in an executive control system that monitors perceptual input. On the other hand, routine, non-conscious perception merely provides data about the world, which indicatively describes the world correctly or incorrectly. Perceptual experience instead involves data that are about the perceiver, not the world. Their (...) function is that of imperatively prompting the perceiver herself to do something (hence. (shrink)
Hegel's discussion of the concept of “habit” appears at a crucial point in his Encyclopedia system, namely, in the transition from the topic of “nature” to the topic of “spirit” (Geist): it is through habit that the subject both distinguishes itself from its various sensory states as an absolute unity (the I) and, at the same time, preserves those sensory states as the content of sensory consciousness. By calling habit a “second nature,” Hegel highlights the fact that incipient spirit (...) retains a “moment” of the natural that marks a limitation compared to “pure thought” but that also makes perceptual consciousness possible. This makes Hegel's account analogous in important respects to John McDowell's “naturalism of second nature.” But Hegel's account of habit can be seen as a version of a Kantian synthesis of the productive imagination—and hence presupposes a given material that can become one's own by means of habit. This does not mean that Hegel falls into the Myth of the Given, but it does suggest that an appropriate account of second nature might be committed to something McDowell wants to deny: that nonconceptual states of consciousness play a role (even if not a justificatory role) in perception. (shrink)
Constructivism undermines realism by arguing that experience is mediated by concepts, and that there is no direct way to examine those aspects of objects that belong to them independently of our conceptualizations; perception is theory-laden. To defend realism one has to show first that perception relates us directly with the world without any intermediary conceptual framework. The result of this direct link is the nonconceptual content of experience. Second, one has to show that part of the nonconceptual content extracted from (...) the environment correctly represents features of mind independent objects. With regard to the first condition, I have argued elsewhere that a part of visual processing, which I call “perception,” is theory-neutral and nonconceptual. In this paper, facing the second demand, I argue that a part of the nonconceptual content of perception presents properties that are the properties of mind independent objects. I claim first that nonconceptual content is the appropriate level of analysis of the issue of realism since it avoids the main problems besetting various types of analysis of the issue at the level of beliefs about the world. Then I claim that a subset of the nonconceptual content presents features of objects in the environment as they really are. (shrink)
Many recent cognitive studies reveal that human cognition is inherently perceptual, sharing systems with perception at both the conceptual and the neural levels. This paper introduces Barsalou's theory of perceptual symbols and explores its implications for philosophy of science. If perceptual symbols lie in the heart of conceptual processing, the process of attribute selection during concept representation, which is critical for defining similarity and thus for comparing taxonomies, can no longer be determined solely by background beliefs. The (...) analogous nature of perceptual symbols and the spatial nature of intraconceptual relations impose new constraints on attribute selection. These constraints help people with different background beliefs select compatible attributes, which constitute a common "platform" for taxonomy comparison. (shrink)
Norman's identification of a ventral system embodying a constructivist theory of perception is rejected in favor of an ecological theory of perception and perceptual learning. We summarize research showing that a key motivation for the ventral-constructivist connection, percept-percept coupling, confuses perceptual and post-perceptual processes.
Stoffregen & Bardy (S&B) make the point that the statement “I am moving” made by subjects in a “swinging room” cannot be explained as an illusion of motion, and there is thus no perceptual illusion. In this they are correct. There is in fact motion, but of the environment. We argue that the subjects misinterpret this because the information to the visual system is ambiguous and also deceiving.
To see whether the mental and the neural have common attributes that could resolve some of the traditional dichotomies, we review neuroscientific data on the visual system. The results show that neuronal and perceptual function share a parallel and hierarchical architecture which is manifest not only in the anatomy and physiology of the visual system, but also in normal perception and in the deficits caused by lesions in different parts of the system. Based on the description (...) of parallel hierarchical levels of active information processing in the visual brain, we suggest a concept of dissociable levels of perception, advocating that the phenomenal perception and recognition is realized in the functional integrity of a network of reciprocal cortico-cortical connections. The properties shared by neuronal and perceptional functions provide a basis for a neuromental monism in which both functions are attributed a causal role. (shrink)
Chaotic itinerancy is useful for illustrating transitions in attractor dynamics seen in the olfactory system. Cantor coding is a good model for information processing, but so far it lacks perceptual proof. The theories presented provide a large step toward bridging the use of chaos as an interpretive tool and hard examination of chaotic neural activity during perception.
Focus+Context techniques are commonly used in visualization systems to simultaneously provide both the details and the context of a particular dataset. This paper proposes a new methodology to empirically investigate the effect of various Focus+Context transformations on human perception. This methodology is based on the shaker paradigm, which tests performance for a visual task on an image that is rapidly alternated with a transformed version of itself. An important aspect of this technique is that it can determine two different kinds (...) of perceptual cost: (i) the effect on the perception of a static transformed image, and (ii) the effect of the dynamics of the transformation itself. This technique has been successfully applied to determine the extent to which human perception is invariant to scaling and rotation [Rensink 2004]. In this paper, we extend this approach to examine nonlinear fisheye transformations of the type typically used in a Focus+Context system. We show that there exists a no-cost zone where performance is unaffected by an abrupt, noticeable fisheye transformation, and that its extent can be determined. The lack of perceptual cost in regards to these sudden changes contradicts the belief that they are necessarily detrimental to performance, and suggests that smoothly animated transformations between visual states are not always necessary. We show that this technique also can map out low-cost zones where transformations result in only a slight degradation of performance. Finally, we show that rectangular grids have no positive effect on performance, acting only as a form of visual clutter. These results therefore demonstrate that the perceptual costs of nonlinear transformations can be successfully quantified. Interestingly, they show that some kinds of sudden transformation can be experienced with minimal or no perceptual cost. This contradicts the belief that sudden changes are necessarily detrimental to performance, and suggests that smoothly animated transformations between visual states are not always necessary.. (shrink)
Focus+Context techniques are commonly used in visualization systems to simultaneously provide both the details and the context of a particular dataset. This paper proposes a new methodology to empirically investigate the effect of various Focus+Context transformations on human perception. This methodology is based on the shaker paradigm, which tests performance for a visual task on an image that is rapidly alternated with a transformed version of itself. An important aspect of this technique is that it can determine two different kinds (...) of perceptual cost: (i) the effect on the perception of a static transformed image, and (ii) the effect of the dynamics of the transformation itself. This technique has been successfully applied to determine the extent to which human perception is invariant to scaling and rotation [Rensink 2004]. In this paper, we extend this approach to examine nonlinear fisheye transformations of the type typically used in a Focus+Context system. We show that there exists a no-cost zone where performance is unaffected by an abrupt, noticeable fisheye transformation, and that its extent can be determined. The lack of perceptual cost in regards to these sudden changes contradicts the belief that they are necessarily detrimental to performance, and suggests that smoothly animated transformations between visual states are not always necessary. We show that this technique also can map out low-cost zones where transformations result in only a slight degradation of performance. Finally, we show that rectangular grids have no positive effect on performance, acting only as a form of visual clutter. These results therefore demonstrate that the perceptual costs of nonlinear transformations can be successfully quantified. Interestingly, they show that some kinds of sudden transformation can be experienced with minimal or no perceptual cost. This contradicts the belief that sudden changes are necessarily detrimental to performance, and suggests that smoothly animated transformations between visual states are not always necessary.. (shrink)
The spokesperson in the Pentagon press room announces the availability of a breakthrough new technology. She says it is the first brain-implantable product of a larger project for developing cybernetic organisms (cyborgs) with new and enhanced sensory capabilities that will also have civilian uses. On the screen we see a device fitted on the forehead of a cyborg that appears to have hardwired connections to the brain on several points on the skull. The spokesperson calls the device.
The paper is focused on the problem of identification in perception. I attempt to inquire on what ground the cognitive system is able to identify an object of perception (I restrict my analysis to visual perception). Although this is an empirical question for cognitive science, I consider it using a philosophical method of analysis. But my considerations in great part are heuristic, I ask questions and rather search for the answers than give a ready solution. The questions I ask (...) arise from a theoretical philosophical inquiry made in the context of cognitive science. The key question of my paper is whether perceptual identification has any cognitive basis, i.e. does it require any concepts or any prior knowledge. I especially pay attention to the problem of representation, asking if perceptual identification is representational or not. These questions are topical today and show that the traditional philosophical approaches to perception require revision and a new critical look at old problems and controversies. (shrink)
The main thesis of the paper is very simple, namely that the cognitive system is a representational system. The cognitive system will be defined as a system which is able to realize cognitive functions such as perception, symbolic thinking, understanding and reflection. Such a system is further characterized as: cognitively open and at the same time relatively isolated, representational, structurally complex and many-dimensional, dynamic and having functional plasticity (cognitively adaptive) and also having the capacity for (...) self-determination. The analysis will be focused on the characterization of representation (which will be defined as a certain kind of content) and on the types of representations in the cognitive system (i.e. perceptual and conceptual representations, the representation of the body and the representation of "self"). (shrink)
Recently, the thesis that experience is fundamentally a matter of representing the world as being a certain way has been questioned by austere relationalists. I defend this thesis by developing a view of perceptual content that avoids their objections. I will argue that on a relational understanding of perceptual content, the fundamental insights of austere relationalism do not compete with perceptual experience being representational. As it will show that most objections to the thesis that experience has content (...) apply only to accounts of perceptual content on which perceptual relations to the world play no explanatory role. With austere relationalists, I will argue that perceptual experience is fundamentally relational. But against austere relationalists, I will argue that it is fundamentally both relational and representational. (shrink)
This paper offers a general reply to arguments from perceptual distortion (e.g. blur, perspective, double vision) against the representationalist thesis that the phenomenal characters of experiences supervene on their intentional contents. It has been argued that distorted and undistorted experiences are counterexamples to this thesis because they can share contents without sharing phenomenal characters. In reply, I suggest that cases of perceptual distortion do not constitute counterexamples to the representationalist thesis because the contents of distorted experiences are always (...) impoverished in some way compared to those of normal experiences. This is can be shown by considering limit cases of perceptual distortion, for example, maximally blurry experiences, which manifestly lack detailed content. I argue that since there is no reasonable way to draw the line between distorted experiences that have degraded content and distorted experiences that don't, we should allow that an increase in distortion is always accompanied by a degradation in content. I also discuss the prospects for a positive account of the contents specific to distorted experiences, which I argue are dim, but for reasons that should not throw doubt on the representationalist thesis. (shrink)
I argue that any account of perceptual experience should satisfy the following two desiderata. First, it should account for the particularity of perceptual experience, that is, it should account for the mind-independent object of an experience making a difference to individuating the experience. Second, it should explain the possibility that perceptual relations to distinct environments could yield subjectively indistinguishable experiences. Relational views of perceptual experience can easily satisfy the first but not the second desideratum. Representational views (...) can easily satisfy the second but not the first desideratum. I argue that to satisfy both desiderata perceptual experience is best conceived of as fundamentally both relational and representational. I develop a view of perceptual experience that synthesizes the virtues of relationalism and representationalism, by arguing that perceptual content is constituted by potentially gappy de re modes of presentation. (shrink)
The paper develops a conception of epistemic warrant as applied to perceptual belief, called "entitlement", that does not require the warranted individual to be capable of understanding the warrant. The conception is situated within an account of animal perception and unsophisticated perceptual belief. It characterizes entitlement as fulfillment of an epistemic norm that is apriori associated with a certain representational function that can be known apriori to be a function of perception. The paper connects anti-individualism, a thesis about (...) the nature of mental states, and perceptual entitlement. It presents an argument that explains the objectivity and validity of perceptual entitlement partly in terms of the nature of perceptual states–hence the nature of perceptual beliefs, which are constitutively associated with perceptual states. The paper discusses ways that an individual can be entitled to perceptual belief through its connection to perception, and ways that entitlement to perceptual belief can be undermined. (shrink)
The consensus in contemporary philosophy of mind is that how a perceptual experience represents the world to be is built into its sensory phenomenology. I defend an opposing view which I call ‘moderate separatism’, that an experience's sensory phenomenology does not determine how it represents the world to be. I argue for moderate separatism by pointing to two ordinary experiences which instantiate the same sensory phenomenology but differ with regard to their intentional content. Two experiences of an object reflected (...) in a mirror can possess the same spatial phenomenology while representing that object to occupy different spatial locations. So, contrary to the current consensus, the representation of spatial location is not fixed by an experience's sensory phenomenology. (shrink)
In this paper I argue that perceptual ascriptions lend themselves to intensional readings, and that perceptual predicates can denote phenomenal states on such readings. I show that Montague's treatment of quantification in intensional contexts applies to intensional perceptual ascriptions. I conclude with some remarks on the implications of these findings for disjunctive and non-disjunctive theories of perceptual experience.
As I use the term, ‘entitlement’ is any warrant one has by default—i.e. without acquiring it. Some philosophers not only affirm the existence of entitlement, but also give it a crucial role in the justification of our perceptual beliefs. These philosophers affirm the Entitlement Thesis: An essential part of what makes our perceptual beliefs justified is our entitlement to the proposition that I am not a brain-in-a-vat. Crispin Wright, Stewart Cohen, and Roger White are among those who endorse (...) this controversial claim. In this paper, I argue that the Entitlement Thesis is false. (shrink)
I argue that perceptual content is always affected by the allocation of one’s attention. Perception attributes determinable and determinate properties to the perceived scene. Attention makes (or tries to make) our perceptual attribution of properties more determinate. Hence, a change in our attention changes the determinacy of the properties attributed to the perceived scene.
The tracking theory treats knowledge as counterfactual covariation of belief and truth through a sphere of possibilities. I argue that the tracking theory cannot respect perceptual knowledge, because perceptual belief covaries with truth through a discontinuous scatter of possibilities.
Perceptual content is conceptual. In this paper, some arguments against this thesis are examined and rebutted. The Richness argument, that we could not have concepts for all the colours, is queried: Doesn't the Munsell system give us such concepts? The argument that we can perceive colours and shapes without possessing the relevant concepts is rebutted: we cannot do this, but the kind of concept-possession that is relevant here is not intellectual but perceptual.
The Perceptual Hypothesis is that we sometimes see, and thereby have non-inferential knowledge of, others' mental features. The Perceptual Hypothesis opposes Inferentialism, which is the view that our knowledge of others' mental features is always inferential. The claim that some mental features are embodied is the claim that some mental features are realised by states or processes that extend beyond the brain. The view I discuss here is that the Perceptual Hypothesis is plausible if, but only if, (...) the mental features it claims we see are suitably embodied. Call this Embodied Perception Theory. I argue that Embodied Perception Theory is false. It doesn't follow that the Perceptual Hypothesis is implausible. The considerations which serve to undermine Embodied Perception Theory serve equally to undermine the motivations for assuming that others' mental lives are always imperceptible. (shrink)
This is an excerpt of a report that highlights and explores five questions that arose from the Network for Sensory Research workshop on perceptual learning and perceptual recognition at the University of York in March, 2012. This portion of the report explores the question: Can perceptual experience be modified by reason?
This report highlights and explores five questions that arose from the Network for Sensory Research workshop on perceptual learning and perceptual recognition at the University of York on March 19th and 20th, 2012: 1. What is perceptual learning? 2. Can perceptual experience be modified by reason? 3. How does perceptual learning alter perceptual phenomenology? 4. How does perceptual learning alter the contents of perception? 5. How is perceptual learning coordinated with action?
This is an excerpt from a report that highlights and explores five questions which arose from the workshop on perceptual learning and perceptual recognition at the University of Toronto, Mississauga on May 10th and 11th, 2012. This excerpt explores the question: What counts as cognitive penetration?
Empirical assessments of Cognitive Behavioral Theory and theoretical considerations raise questions about the fundamental theoretical tenet that psychological disturbances are mediated by consciously accessible cognitive structures. This paper considers this situation in light of emotion theory in philosophy. We argue that the “perceptual theory” of emotions, which underlines the parallels between emotions and sensory perceptions, suggests a conception of cognitive mediation that can accommodate the observed empirical anomalies and one that is consistent with the dual-processing models dominant in cognitive (...) psychology. (shrink)
This report highlights and explores five questions which arose from the workshop on perceptual learning and perceptual recognition at the University of Toronto, Mississauga on May 10th and 11th, 2012: 1. How should we demarcate perceptual learning from perceptual development? 2. What are the origins of multimodal associations? 3. Does our representation of time provide an amodal framework for multi-sensory integration? 4. What counts as cognitive penetration? 5. How can philosophers and psychologists most fruitfully collaborate?
Abstract: Each affective state has distinct motor-expressions, sensory perceptions, autonomic, and cognitive patterns. Panksepp (1998) proposed seven neural affective systems of which the SEEKING system, a generalized approach-seeking system, motivates organisms to pursue resources needed for survival. When an organism is presented with a novel stimulus, the dopamine (DA) in the nucleus accumbens septi (NAS) is released. The DA circuit outlines the generalized mesolimbic dopamine-centered SEEKING system and is especially responsive when there is an element of unpredictability (...) in forthcoming rewards. We propose that when the outcome of this interaction is unexpected or unanticipated then Panksepp’s “cognitive or expectancy reset” mechanism involving the cognitive dissonance would yield the subjective emotion of surprise. In order to appropriately react to the environment’s stimuli one needs fundamental processes that would enable one to distinguish between what is novel and what has been already experienced, as well as the different degrees of novelty. Novel events are those whose essential features of the representation (visceral and perceptual) are altered and being discrepant provoke more sustained attention. Novelty arises from salient and arousing events and the organism experiences surprise, as coming out of a habitual state. In this framework, we shall look at established theories of emotions and propose a different approach to their taxonomy. (shrink)
This is an excerpt of a report that highlights and explores five questions that arose from the Network for Sensory Research workshop on perceptual learning and perceptual recognition at the University of York in March, 2012. This portion of the report explores the question: How does perceptual learning alter perceptual phenomenology?
This is an excerpt of a report that highlights and explores five questions that arose from the Network for Sensory Research workshop on perceptual learning and perceptual recognition at the University of York in March, 2012. This portion of the report explores the question: What is perceptual learning?
I open my eyes and see that the lemon before me is yellow. States like this—states of seeing that p —appear to be visual perceptual states, in some sense. They also appear to be propositional attitudes (and so states with propositional representational contents). It might seem, then, like a view of perceptual experience on which experiences have propositional representational contents—a Propositional View—has to be the correct sort of view for states of seeing that p . And thus we (...) can’t sustain fully general non-Propositional but Representational, or Relational Views of experience. But despite what we might initially be inclined to think when reflecting upon the apparent features of states of seeing that p , a non-propositional view of seeing that p is, I argue, perfectly intelligible. (shrink)
This is an excerpt of a report that highlights and explores five questions that arose from the Network for Sensory Research workshop on perceptual learning and perceptual recognition at the University of York in March, 2012. This portion of the report explores the question: How does perceptual learning alter the contents of perception?
This is an excerpt of a report that highlights and explores five questions that arose from the Network for Sensory Research workshop on perceptual learning and perceptual recognition at the University of York in March, 2012. This portion of the report explores the question: How is perceptual learning coordinated with action?
The control of action has traditionally been described as "automatic". In particular, movement control may occur without conscious awareness, in contrast to normal visual perception. Studies on rapid visuomotor adjustment of reaching movements following a target shift have played a large part in introducing such distinctions. We suggest that previous studies of the relation between motor performance and perceptual awareness have confounded two separate dissociations. These are: (a) the distinction between motoric and perceptual representations, and (b) an orthogonal (...) distinction between conscious and unconscious processes. To articulate these differences more clearly, we propose a new measure of motor awareness, based on subjects' ability to reproduce the spatial details of reaching movements they have just made. Here we focus on the dissociation between motor awareness and perceptual awareness that may occur when subjects make rapid visuomotor adjustments to reaching movements following a target shift. In experiment 1, motor awareness was dissociated from perceptual awareness of a target shift during reaching movement. Participants' reproduction of movement endpoints following visuomotor adjustment was independent of whether they saw the target shift or not. Experiment 2 replicated this result, and further showed that neither motor awareness nor motor performance were disrupted by TMS over the parietal cortex. The neural mechanisms underlying motor awareness, and the implications for theories of consciousness, are discussed. (shrink)
This is an excerpt from a report that highlights and explores five questions which arose from the workshop on perceptual learning and perceptual recognition at the University of Toronto, Mississauga on May 10th and 11th, 2012. This excerpt explores the question: Does our representation of time provide and amodal framework for multi-sensory integration?
This is an excerpt from a report that highlights and explores five questions which arose from the workshop on perceptual learning and perceptual recognition at the University of Toronto, Mississauga on May 10th and 11th, 2012. This excerpt explores the question: How should we demarcate perceptual learning from perceptual development?
John McDowell and Bill Brewer famously defend the view that one can only have empirical beliefs if one’s perceptual experiences serve as reasons for such beliefs, where reasons are understood in terms of subject’s reasons. In this paper I show, first, that it is a consequence of the adoption of such a requirement for one to have empirical beliefs that children as old as 3 years of age have to considered as not having genuine empirical beliefs at all. But (...) we have strong reasons to think that 3-year-old children have empirical beliefs, or so I argue. If this is the case, McDowell and Brewer’s requirement for one to have empirical beliefs faces a strong challenge. After showing this, I propose an alternative requirement for one to have empirical beliefs, and argue that it should be favoured over McDowell and Brewer’s requirement. (shrink)
This is an excerpt from a report that highlights and explores five questions which arose from the workshop on perceptual learning and perceptual recognition at the University of Toronto, Mississauga on May 10th and 11th, 2012. This excerpt explores the question: What are the origins of multimodal associations?
This is an excerpt from a report that highlights and explores five questions which arose from the workshop on perceptual learning and perceptual recognition at the University of Toronto, Mississauga on May 10th and 11th, 2012. This excerpt explores the question: How can philosophers and psychologists most fruitfully collaborate?
Philosophy is a way of being in the world of questions, interacting with it, and responding to it. Human mind is an ongoing dialogue about the topics of philosophy such as good and evil, right and wrong, truth and falsity, appearance and reality. Education refers to an act or experience that has a formative effect on the mind, character, physical ability of an individual. Values are whatever an individual desires, prefers and likes. In context of present education system moral, (...) cultural and spiritual values should be preferred. New Education Policy of India should be built on the foundation of ancient spiritualistic, modern culture and technical sophistication. It should develop scientific temper and spirit of inquiry in the students also. The present work entitled, “Philosophy, Education and Indian Value System” is an attempt to relate philosophy, education and values at the same ground, so that they can perform the conception of complete education. Here we have three chapters i.e. (i) Philosophy and Values in School Education of India, Sri Aurobindo’s Philosophy of Education and Spiritual Approach to Education: An Indian Experience, respectively. I would like to thank my students and colleagues of Milestone Education Society (Regd.) Pehowa for their full time support and corporation in our educational programmes. (shrink)
A straightforward way of thinking about perception is in terms of perceptual representation. Perception is the construction of perceptual representations that represent the world correctly or incorrectly. This way of thinking about perception has been questioned recently by those who deny that there are perceptual representations. This article examines some reasons for and against the concept of perceptual representation and explores some potential ways of resolving this debate. Then it analyzes what perceptual representations may be: (...) if they attribute properties to entities, what are these attributed properties, and what are the entities they are attributed to. (shrink)
In this paper we focus on the modularity of visual functions in the human visual cortex, that is, the specific problems that the visual system must solve in order to achieve recognition of objects and visual space. The computational theory of early visual functions is briefly reviewed and is then used as a basis for suggesting computational constraints on the higher-level visual computations. The remainder of the paper presents neurological evidence for the existence of two visual systems in man, (...) one specialized for spatial vision and the other for object vision. We show further clinical evidence for the computational hypothesis that these two systems consist of several visual modules, some of which can be isolated on the basis of specific visual deficts which occur after lesions to selected areas in the visually responsive brain. We will provide examples of visual modules which solve information processing tasks that are mediated by specific anatomic areas. We will show that the clinical data from behavioral studies of monkeys (Ungerleider and Mishkin 1984) supports the distinction between two visual systems in monkeys, the 'what' system, involved in object vision, and the 'where' system, involved in spatial vision. (shrink)
Perceptual reports are utterances of sentences that contain a perceptual verb, such as ‘look’, ‘sound’, ‘feel’, ‘see’, and ‘perceive’. It is natural to suppose that at least in many cases, these types of reports reflect aspects of the phenomenal character and representational content of a subject’s perceptual experiences. For example, an utterance of ‘my chair looks red but it’s really white’ appears to reflect phenomenal properties of the speaker’s experience of a chair. Whether perceptual reports actually (...) reflect these things is a substantial question and one with which this entry will be partially concerned. This article begins with a linguistic analysis of perceptual verbs and then considers some potential implications of this analysis for the philosophy of perception, given the assumption that perceptual reports sometimes express truths. (shrink)
One holistic thesis about symbols is that a symbol cannot exist singly, but only as apart of a symbol system. There is also the plausible view that symbol systems emerge gradually in an individual, in a group, and in a species. The problem is that symbol holism makes it hard to see how a symbol system can emerge gradually, at least if we are considering the emergence of a first symbol system. The only way it seems possible (...) is if being a symbol can be a matter of degree, which is initially problematic. This article explains how being a cognitive symbol can be a matter of degree after all. The contrary intuition arises from the way a process of interpretation forces an all-or-nothing character on symbols, leaving room for underlying material to realize symbols to different degrees in a way that Daniel Dennett’s work can help illuminate. Holism applies to symbols as interpreted, while gradualism applies to how the underlying material realizes symbols.Selon une thèse holistique sur les symboles, un symbole ne peut exister isolément mais doit faire partie d’un systéme symbolique. Une opinion, elle aussi plausible, veut que les systèmes symboliques émergent graduellement chez un individu, un groupe ou une espèce. Le problème c’est qu’on voit mal, si le holisme des systèmes symboliques tient, comment un système symbolique peut émerger graduellement, du moins pour la première fois. Ce n’est possible, semble-t-il, que si être un symbole est affaire de degré, thèse au départ problématique. Cet article explique comment être un symbole cognitif peut après tout être affaire de degré. L’intuition contraire vient de ce que le processus d’interprétation nous force au tout ou rien, ce qui laisse un jeu dans la façon dont le matériel sous-jacent réalise les symboles à des degrés divers. Les travaux de Daniel Dennett sont à cet égard éclairants. Le holisme vaut pour les symboles tels qu’ils sont interprétés, tandis que le gradualisme vaut pour la façon dont le matériel sous-jacent réalise les symboles. (shrink)
The focus of this commentary is what Andy Clark takes to be the most groundbreaking of the philosophical import of the ‘bidirectional hierarchical model of brain functions’, namely, the claim that perceptual representations represent probabilities. This is what makes his account Bayesian and this is a philosophical or theoretical conclusion that neuroscientists and psychologists are also quick and happy to draw. My claim is that nothing in the ‘bidirectional hierarchical models of brain functions’ implies that perceptual representations are (...) probabilistic, or that they represent or ‘encode probability density distributions’. There is a much more parsimonious way of describing the representations in the bidirectional hierarchical model of brain functions: they attribute properties to objects (or to the perceived scene) that are not fully determinate. (shrink)
Complex systems research is becoming ever more important in both the natural and social sciences. It is commonly implied that there is such a thing as a complex system, different examples of which are studied across many disciplines. However, there is no concise definition of a complex system, let alone a definition on which all scientists agree. We review various attempts to characterize a complex system, and consider a core set of features that are widely associated with (...) complex systems in the literature and by those in the field. We argue that some of these features are neither necessary nor sufficient for complexity, and that some of them are too vague or confused to be of any analytical use. In order to bring mathematical rigour to the issue we then review some standard measures of complexity from the scientific literature, and offer a taxonomy for them, before arguing that the one that best captures the qualitative notion of the order produced by complex systems is that of the Statistical Complexity. Finally, we offer our own list of necessary conditions as a characterization of complexity. These conditions are qualitative and may not be jointly sufficient for complexity. We close with some suggestions for future work. (shrink)
Recent evidence from cognitive neuroscience suggests that certain cognitive processes employ perceptual representations. Inspired by this evidence, a few researchers have proposed that cognition is inherently perceptual. They have developed an innovative theoretical approach that rests on the notion of perceptual simulation and marshaled several general arguments supporting the centrality of perceptual representations to concepts. In this article, I identify a number of weaknesses in these arguments and defend a multiple semantic code approach that posits both (...)perceptual and non-perceptual representations. (shrink)
The objective of this paper is to analyse, from a philosophical perspective, the 16th and 17th Century models of currency, as well as their influence on the types of society in which the models developed. For this, the author values the study by the French philosopher Michael Foucault Words and Things on this matter and the principal foundations of Ludwig von Bertalanffy´s systems theory. The 17th Century model of currency is based on the notion of a system of exchange. (...) The notion of a system of exchange represents a transformation of great significance, upon which the principal characteristics of our current globalised era are founded, not only in economic life, but also in relation to an understanding of the world that it implies. Furthermore, the notion of a system of exchange was the step before the current model of electronic payments of the digital era, in which large transactions (and also large data transfers) take place by pressing a button. The principal idea of the paper is that these economic practices hold the key to deepen a philosophical and historical comprehension of concepts such as globalisation. (shrink)
The article discusses issues explaining the effectiveness of practical application of mathematical results. The proposed approach is based on Leibnizâs metaphysics, a modern system theory and non-rational view of selection criteria in the âfuture needsâ models.
Having entered into the problem structuring methods, system dynamics (SD) is an approach, among systems’ methodologies, which claims to recognize the main structures of socio-economic behaviors. However, the concern for building or discovering strong philosophical underpinnings of SD, undoubtedly playing an important role in the modeling process, is a long-standing issue, in a way that there is a considerable debate about the assumptions or the philosophical foundations of it. In this paper, with a new perspective, we have explored theory (...) of knowledge in SD models and found strange similarities between classic epistemological concepts such as justification and truth, and the mechanism of obtaining knowledge in SD models. In this regard, we have discussed related theories of epistemology and based on this analysis, have suggested some implications for moderating common problems in the modeling process of SD. Furthermore, this research could be considered a reword of system dynamics modeling principles in terms of theory of knowledge. (shrink)
The fundamental concept of structured chemical system has been introduced and analysed in this paper. This concept, as in biology but not in physics, is very important in chemistry. In fact, the main chemical concepts (molecule and compound) have been identified as systemic concepts and their use in chemical explanation can only be justified in this approach. The fundamental concept of “environment” has been considered and then the system concept in mechanics, chemistry and biology. The differences and the (...) analogies between the use of the systemic approach in these disciplines have been analyzed and correlated to the general problem of reductionism and complexity perspectives. The inanimate–animate dichotomy can be reconsidered in this new approach. Since the chemical systemic concepts of molecule and compound can be dated to the nineteenth century, chemistry can be considered the first true systemic science and its historical evolution can be a model for other sciences (such as the humanities) where the systemic concepts are important. (shrink)
The two contrasting theoretical approaches to visual perception, the constructivist and the ecological, are briefly presented and illustrated through their analyses of space and size perception. Earlier calls for their reconciliation and unification are reviewed. Neurophysiological, neuropsychological, and psychophysical evidence for the existence of two quite distinct visual systems, the ventral and the dorsal, is presented. These two perceptual systems differ in their functions; the ventral system's central function is that of identification, while the dorsal system is (...) mainly engaged in the visual control of motor behavior. The strong parallels between the ecological approach and the functioning of the dorsal system, and between the constructivist approach and the functioning of the ventral system are noted. It is also shown that the experimental paradigms used by the proponents of these two approaches match the functions of the respective visual systems. A dual-process approach to visual perception emerges from this analysis, with the ecological-dorsal process transpiring mainly without conscious awareness, while the constructivist-ventral process is normally conscious. Some implications of this dual-process approach to visual-perceptual phenomena are presented, with emphasis on space perception. Key Words: constructivist; dual-process approach; ecological; size perception; space perception; two visual systems; visual perception theories. (shrink)
Our perceptual systems make information about the world available to our cognitive faculties. We come to think about the colors and shapes of objects because we are built somehow to register the instantiation of these properties around us. Just how we register the presence of properties and come to think about them is one of the central problems with understanding perceptual cognition. Another problem in the philosophy of perception concerns the nature of the properties whose presence we register. (...) Among the perceptible properties are colors and shapes, for example, and there is a long philosophical tradition of drawing and refusing to draw metaphysical distinctions between them. This paper makes a claim about the information-theoretic approach to perceptual cognition in order to argue for a fundamentally epistemological distinction between colors and shapes. What makes shapes and colors seem so different to us is how we carry information about their presence around us. In particular, we can come to know more about the shapes on the basis of perceiving them than we can come to know about the colors. One interesting feature of how this distinction is drawn is that it partially vindicates Locke’s claim that our ideas of primary qualities like shapes resemble them in ways our ideas of colors do not. (shrink)
Modality specificity in priming is taken as evidence for independent perceptual systems. However, Easton, Greene, and Srinivas (1997) showed that visual and haptic cross-modal priming is comparable in magnitude to within-modal priming. Where appropriate, perceptual systems might share like information. To test this, we assessed priming and recognition for visual and auditory events, within- and across- modalities. On the visual test, auditory study resulted in no priming. On the auditory priming test, visual study resulted in priming that was (...) only marginally less than within-modal priming. The priming results show that visual study facilitates identification on both visual and auditory tests, but auditory study only facilitates performance on the auditory test. For both recognition tests, within-modal recognition exceeded cross-modal recognition. The results have two novel implications for the understanding of perceptual priming: First, we introduce visual and auditory priming for spatio-temporal events as a new priming paradigm chosen for its ecological validity and potential for information exchange. Second, we propose that the asymmetry of the cross-modal priming observed here may reflect the capacity of these perceptual modalities to provide cross-modal constraints on ambiguity. We argue that visual perception might inform and constrain auditory processing, while auditory perception corresponds to too many potential visual events to usefully inform and constrain visual perception. (shrink)
This is an important new critical analysis of Derrida's theory of writing, based on close readings of key texts. It reveals a dimension of Derrida's thinking that has been neglected in favor of those "deconstructionist" cliches favored by much recent literary criticism. Christopher Johnson highlights the special character of Derrida's philosophy that comes from his contact with contemporary natural science and with systems theory. This study casts new light on an exacting set of intellectual issues facing philosophy and critical theory (...) today. (shrink)
Where in cognitive architecture do experiences of agency lie? This chapter defends the claim that such states qualify as a species of perception. Reference to ‘the sense of agency’ should not be taken as a mere façon de parler but picks out a genuinely perceptualsystem. The chapter begins by outlining the perceptual model of agentive experience before turning to its two main rivals: the doxastic model, according to which agentive experience is really a species of belief, (...) and the telic model, according to which agentive experience is really a species of agency. I conclude by defending the perceptual model against a number of objections to it, and by briefly exploring its implications for the question of how to approach the study of perception. (shrink)
Happiness, like other basic emotions, has visual properties that create the conditions for happiness to be perceived in others. This is to say that happiness is perceivable. Its visual properties are to be identified with those facial expressions that are characteristic of happiness. Yet saying that something is perceivable does not suffice for us to conclude that it is perceived. We therefore need to show that happiness is perceived. Empirical evidence suggests that the visual system functions to perceive happiness (...) as well as other basic emotions. Experiences that can be had simply by virtue of how the perceptualsystem functions are known as observations. I will thus argue that visual experiences in which we become aware of others’ happiness are observations. This approach will provide the necessary conceptual framework to show that we have perceptual knowledge of others’ happiness. (shrink)
Much contemporary discussion of perceptual experience can be traced to two observations. The first is that perception seems to put us in direct contact with the world around us: when perception is successful, we come to recognize— immediately—that certain objects have certain properties. The second is that perceptual experience may fail to provide such knowledge: when we fall prey to illusion or hallucination, the way things appear may differ radically from the way things actually are. For much of (...) the twentieth century, many of the most important discussions of perceptual experience could be fruitfully understood as responses to this pair of observations. (shrink)
Perceptual theories of emotion purport to avoid the problems of traditional cognitivism and noncognitivism by modelling emotion on perception, which shares the most conspicuous dimensions of emotion, intentionality and phenomenality. In this paper, I shall reconstrue and discuss four key arguments that perceptual theorists have presented in order to show that emotion is a kind of perception, or that there are close analogies between emotion and perception. These arguments are, from stronger to weaker claims: the perceptual (...) class='Hi'>system argument; the argument from noninferential structure; the argument from epistemic role; and the argument from phenomenology. I argue that, while the arguments in favour of assimilating emotion to perception fail, the analogies between emotion and perception are not as close as perceptual theorists suggest even if some emotions resemble perception more than others, thanks to the two-levelled structure of emotional processing. (shrink)
Various defenses of amodal symbol systems are addressed, including amodal symbols in sensory-motor areas, the causal theory of concepts, supramodal concepts, latent semantic analysis, and abstracted amodal symbols. Various aspects of perceptual symbol systems are clarified and developed, including perception, features, simulators, category structure, frames, analogy, introspection, situated action, and development. Particular attention is given to abstract concepts, language, and computational mechanisms.
Circumscribed delusional beliefs can follow brain injury. We suggest that these involve anomalous perceptual experiences created by a deficit to the person's perceptualsystem, and misinterpretation of these experiences due to biased reasoning. We use the Capgras delusion (the claim that one or more of one's close relatives has been replaced by an exact replica or impostor) to illustrate this argument. Our account maintains that people voicing this delusion suffer an impairment that leads to faces being perceived (...) as drained of their normal affective significance, and an additional reasoning bias that leads them to put greater weight on forming beliefs that are observationally adequate rather than beliefs that are a conservative extension of their existing stock. We show how this position can integrate issues involved in the philosophy and psychology of belief, and examine the scope for mutually beneficial interaction. (shrink)
The visual brain consists of several parallel, functionally specialized processing systems, each having several stages (nodes) which terminate their tasks at different times; consequently, simultaneously presented attributes are perceived at the same time if processed at the same node and at different times if processed by different nodes. Clinical evidence shows that these processing systems can act fairly autonomously. Damage restricted to one system compromises specifically the perception of the attribute that that system is specialized for; damage to (...) a given node of a processing system that leaves earlier nodes intact results in a degraded perceptual capacity for the relevant attribute, which is directly related to the physiological capacities of the cells left intact by the damage. By contrast, a system that is spared when all others are damaged can function more or less normally. Moreover, internally created visual percepts-illusions, afterimages, imagery, and hallucinations-activate specifically the nodes specialized for the attribute perceived. Finally, anatomical evidence shows that there is no final integrator station in the brain, one which receives input from all visual areas; instead, each node has multiple outputs and no node is recipient only. Taken together, the above evidence leads us to propose that each node of a processing-perceptualsystem creates its own microconsciousness. We propose that, if any binding occurs to give us our integrated image of the visual world, it must be a binding between microconsciousnesses generated at different nodes. Since any two microconsciousnesses generated at any two nodes can be bound together, perceptual integration is not hierarchical, but parallel and postconscious. By contrast, the neural machinery conferring properties on those cells whose activity has a conscious correlate is hierarchical, and we refer to it as generative binding, to distinguish it from the binding that might occur between the microconsciousnesses. (shrink)
This article proposes an object properties approach to object perception. By thinking about objects as clusters of co-instantiated features that possess certain canonical higher-order object properties we can steer a middle way between two extreme views that are dominant in different areas of empirical research into object perception and the development of the object concept. Object perception should be understood in terms of perceptual sensitivity to those object properties, where that perceptual sensitivity can be explained in a manner (...) consistent with the graded representation approach adopted by some connectionist modellers. The object properties approach does justice to the differences between a perceptualsystem solving the binding problem, on the one hand, and genuinely perceiving objects, on the other, without running into the theoretical problems associated with treating young infants as 'little scientists'. (shrink)
We define a mathematical formalism based on the concept of an ‘‘open dynamical system” and show how it can be used to model embodied cognition. This formalism extends classical dynamical systems theory by distinguishing a ‘‘total system’’ (which models an agent in an environment) and an ‘‘agent system’’ (which models an agent by itself), and it includes tools for analyzing the collections of overlapping paths that occur in an embedded agent's state space. To illustrate the way this (...) formalism can be applied, several neural network models are embedded in a simple model environment. Such phenomena as masking, perceptual ambiguity, and priming are then observed. We also use this formalism to reinterpret examples from the embodiment literature, arguing that it provides for a more thorough analysis of the relevant phenomena. (shrink)
In this paper I review some leading developments in the empirical theory of affect. I argue that (1) affect is a distinct perceptual representation governed system, and (2) that there are significant modular factors in affect. The paper concludes with the observation thatfeeler (affective perceptualsystem) may be a natural kind within cognitive science. The main purpose of the paper is to explore some hitherto unappreciated connections between the theory of affect and the computational theory of (...) mind. (shrink)
The psychological concept of illusion is defined as a process involving an interaction of logical and empirical considerations. Common usage suggests that an illusion is a discrepancy between one's awareness and some stimulus. Following preliminary definitions of classes of stimuli, five definitions of illusion are considered, based upon the possible discrepancies between awareness and a stimulus. It is found that each of these definitions fails to make important distinctions, even to the point of equating all illusory and perceptual phenomena. (...) This dilemma is resolved by redefining illusion without reference to truth or falsity, but relative to the functioning of a given perceptualsystem under different conditions. The definition accepted as best is 'a discrepancy between one's perceptions of an object or event observed under different conditions'. Conditions may differ in terms of stimulus exposure, stimulus context, or experiental context. The philosophical and psychological implications are discussed of accepting a definition of illusion not based on a discrepancy between awareness and a stimulus. (shrink)
People are remarkably smart: They use language, possess complex motor skills, make nontrivial inferences, develop and use scientific theories, make laws, and adapt to complex dynamic environments. Much of this knowledge requires concepts and this study focuses on how people acquire concepts. It is argued that conceptual development progresses from simple perceptual grouping to highly abstract scientific concepts. This proposal of conceptual development has four parts. First, it is argued that categories in the world have different structure. Second, there (...) might be different learning systems (subserved by different brain mechanisms) that evolved to learn categories of differing structures. Third, these systems exhibit differential maturational course, which affects how categories of different structures are learned in the course of development. And finally, an interaction of these components may result in the developmental transition from perceptual groupings to more abstract concepts. This study reviews a large body of empirical evidence supporting this proposal. (shrink)
According to a growing trend in theoretical neuroscience, the human perceptualsystem is akin to a Bayesian machine. The aim of this article is to clearly articulate the claims that perception can be considered Bayesian inference and that the brain can be considered a Bayesian machine, some of the epistemological challenges to these claims; and some of the implications of these claims. We address two questions: (i) How are Bayesian models used in theoretical neuroscience? (ii) From the use (...) of Bayesian models in theoretical neuroscience, have we learned or can we hope to learn that perception is Bayesian inference or that the brain is a Bayesian machine? From actual practice in theoretical neuroscience, we argue for three claims. First, currently Bayesian models do not provide mechanistic explanations; instead they are useful devices for predicting and systematizing observational statements about people's performances in a variety of perceptual tasks. That is, currently we should have an instrumentalist attitude towards Bayesian models in neuroscience. Second, the inference typically drawn from Bayesian behavioural performance in a variety of perceptual tasks to underlying Bayesian mechanisms should be understood within the three-level framework laid out by David Marr ( [1982] ). Third, we can hope to learn that perception is Bayesian inference or that the brain is a Bayesian machine to the extent that Bayesian models will prove successful in yielding secure and informative predictions of both subjects' perceptual performance and features of the underlying neural mechanisms. (shrink)
This paper has three aims. First, I’ll argue that there’s no good reason to accept any kind of ‘easy knowledge’ objection to externalist foundationalism. It might be a little surprising that we can come to know that our perception is accurate by using our perception, but any attempt to argue this is impossible seems to rest on either false premises or fallacious reasoning. Second, there is something defective about using our perception to test whether our perception is working. What this (...) reveals is that there are things we aim for in testing other than knowing that the device being tested is working. I’ll suggest that testing aims for sensitive knowledge that the device is working. Testing a device, such as our perceptualsystem, by using its own outputs may deliver knowledge, but it can’t deliver sensitive knowledge. So it’s a bad way to test the system. The big conclusion here is that sensitivity is an important epistemic virtue, although it is not necessary for knowledge. Third, I’ll argue that the idea that sensitivity is an epistemic virtue can provide a solution to a tricky puzzle about inductive evidence. This provides another reason for thinking that the conclusion of section two is correct: not all epistemic virtues are to do with knowledge. (shrink)
