In Section I, I clarify turning point issues in the Phillips and Block debate about whether there is unconscious perception. These include questions about whether uptake of certain visual information is an individual or person level accomplishment, as required for genuine unconscious perceiving. Section II takes up a recent reorientation proposed in Block towards the question of whether there is unconscious perceiving, where we are to look for the pervasive role of unconscious perceiving in, perhaps especially, the online control of (...) everyday reaching and grasping. I point out that while this may well be a helpfully different approach to explore, it does not evade the central questions and challenges familiar from the prior debate between Phillips and Block. Section III reviews an approach summarized in Dehaene, drawing from a range of measures of neural activity. Dehaene provides evidence of quite rich non-conscious perceptual system responses, some arguably individual or person level. But in a fairly thin or fragile way, absent taking up, in higher level assessment, the information encoded in initial visual response. Or that is the interpretation I argue for, in relating the Dehaene account to the Phillips and Block debate, in a way that illuminates the Phillips and Block discussions. An Appendix provides an overview of debates in the literature about the Goodale and Milner Two Visual Systems Hypothesis, that Block makes central appeal to. (shrink)
I develop a Russellian representationalist account of size experience that draws importantly from contemporary vision science research on size perception. The core view is that size is experienced in ‘body-scaled’ units. So, an object might, say, be experienced as two eye-level units high. The view is sharpened in response to Thompson’s (forthcoming) Doubled Earth example. This example is presented by Thompson as part of an argument for a Fregean view of size experience. But I argue that the Russellian view I (...) develop handles the Doubled Earth example in a natural and illuminating way, thereby avoiding the need to posit irreducible experiential ‘modes of presentation’. I also address a kind of neo-Fregean ‘reference-fixing’ view of size experience, that shares features with the Russellian view developed. I give reasons for favoring the latter. Finally, I argue that Peacocke’s claim that spatial experience is ‘unit free’ is not persuasive. (shrink)
Long tradition in philosophy and in empirical psychology has it that the perceptual recovery of enduring objective size and shape proceeds through initial spatial appearance experiences—like the sensed changing visual field size of a receding car, or the shifting shape appearance of a coin as it rotates in depth. The present paper carefully frames and then critically examines such proposals. It turns out that these are contingent, empirical matters, requiring close examination of relevant research in perception science in order to (...) decide. The paper concludes with extended discussions of the empirical study of the perception of slant, size, and shape. (shrink)
A coin rotating back in depth in some sense presents a changing, elliptical shape. How are we to understand such (in this case) ‘appearances of ellipticality’? How is the experiential sense of such shifting shape appearances related to the experiential sense of enduring shape definitive of perceived shape constancy? Is the experiential recovery of surface shape based on the prior (perhaps more fundamental) recovery of point or element 3D spatial locations?—or is the perception of shape a largely independent perceptual achievement? (...) Do we gain access to enduring shape properties by first detecting and working from ‘shape appearances’? These are some of the topics taken up in this paper. (shrink)
One often hears it said that our visual-perceptual contact with the world is “perspectival.” But this can mean quite different things. Three different senses in which our visual contact with the world is “perspectival” are distinguished. The first involves the detection or representation of behaviorally important relations, holding between a perceiving subject and the world. These include time to contact, body-scaled size, egocentric position, and direction of heading. The second perspective becomes at least explicitly manifest in taking up the “proximal (...) mode” and involves the representation of relational “appearance properties,” such as, perhaps , angular size and angular/projective shape at or from a viewpoint. The third perspective is associated with the pencil of rays structured by the position and geometry of the eyes. The relationships between these three perspectives are charted, and their connection with conscious experiential awareness discussed. So, e.g., there is no simple or direct route from the detection of the relations constitutive of perspective2 to detection of the relations constitutive of perspective1. The relations definitive of perspective3 are probably not themselves detected or represented by the visual system, but define the informational arena within which detection of the relations definitive of perspective1 and perspective2 takes place. (shrink)
Philosophers and cognitive scientists address the relationships among the senses and the connections between conscious experiences that form unified wholes. In this volume, cognitive scientists and philosophers examine two closely related aspects of mind and mental functioning: the relationships among the various senses and the links that connect different conscious experiences to form unified wholes. The contributors address a range of questions concerning how information from one sense influences the processing of information from the other senses and how unified states (...) of consciousness emerge from the bonds that tie conscious experiences together. Sensory Integration and the Unity of Consciousness is the first book to address both of these topics, integrating scientific and philosophical concerns. A flood of recent work in both philosophy and perception science has challenged traditional conceptions of the sensory systems as operating in isolation. Contributors to the volume consider the ways in which perceptual contact with the world is or may be “multisensory,” discussing such subjects as the modeling of multisensory integration and philosophical aspects of sensory modalities. Recent years have seen a similar surge of interest in unity of consciousness. Contributors explore a range of questions on this topic, including the nature of that unity, the degree to which conscious experiences are unified, and the relationship between unified consciousness and the self. Contributors Tim Bayne, David J. Bennett, Berit Brogaard, Barry Dainton, Ophelia Deroy, Frederique de Vignemont, Marc Ernst, Richard Held, Christopher S. Hill, Geoffrey Lee, Kristan Marlow, Farid Masrour, Jennifer Matey, Casey O'Callaghan, Cesare V. Parise, Kevin Rice, Elizabeth Schechter, Pawan Sinha, Julia Trommershaeuser, Loes C. J. van Dam, Jonathan Vogel, James Van Cleve, Robert Van Gulick, Jonas Wulff. (shrink)
An empirically based view of size and distance perceptual content and phenomenology is introduced, in which perceivers measure worldly size and distance against their bodies. Central principles of the formal, representational theory of the measurement of extensive magnitudes are then applied in framing the account in a precise way. The question of whether spatial-perceptual experience is “unit-free” is clarified. The framework is used to assess Dennis Proffitt's proposal that spatial setting is perceived in various “units,” “scales,” or “rulers”, some of (...) them non-spatial—distance in terms of calories burned to traverse and the like. The debate between Proffitt and Firestone about the commensurability of differing measurement scales held by Proffitt to be relied on by perceivers is then clarified and resolved. Finally, the measurement theory framed account of size and distance perception is used to illuminate Gibson’s famous but elusive contrasts between “geometrical optics” and “ecological optics” and between the “physical world” and the “animal environment”. (shrink)
Axioms in set theory typically have the form , where is a relation which links with in some way. In this paper we introduce a particular linkage relation and a single axiom based on from which all the axioms of (Zermelo set theory) can be derived as theorems. The single axiom is presented both in informal and formal versions. This calls for some discussion of pertinent features of formal and informal axiomatic method and some discussion of pertinent features of the (...) system of set theory to be erected on the single axiom. is shown to be somewhat stronger than , but much weaker than (Zermelo-Fraenkel set theory). (shrink)
This message was shared by David Bennett as the basis for morning worship on 3–6 July 1995 at the Oxford Centre for Mission Studies Summer School on the subject of Institutional Development in Theological Education in the Two-thirds World. Further studies on friend, brother/sister, servant will appear in the next issue of Transformation.
By age 85, most adults manifest some degree of motor impairment. However, in most individuals a specific etiology for motor decline and treatment to modify its inexorable progression cannot be identified. Recent clinical-pathologic studies provide evidence that mixed-brain pathologies are commonly associated with late-life motor impairment. Yet, while nearly all older adults show some degree of accumulation of Alzheimer’s disease and related dementias pathologies, the extent to which these pathologies contribute to motor decline varies widely from person to person. Slower (...) or faster than expected motor decline in the presence of brain injury and/or pathology has been conceptualized as more or less “resilience” relative to the average person This suggests that other factors, such as lifestyles or other neurobiologic indices may offset or exacerbate the negative effects of pathologies via other molecular pathways. The mechanisms underlying neural motor resilience are just beginning to be illuminated. Unlike its cousin, cognitive resilience which is restricted to neural mechanisms above the neck, the motor system extends the total length of the CNS and beyond the CNS to reach muscle and musculoskeletal structures, all of which are crucial for motor function. Building on prior work, we propose that by isolating motor decline unrelated to neuropathologies and degeneration, investigators can identify genes and proteins that may provide neural motor resilience. Elucidating these molecular mechanisms will advance our understanding of the heterogeneity of late-life motor impairment. This approach will also provide high value therapeutic targets for drug discovery of therapies that may offset the negative motor consequences of CNS pathologies that are currently untreatable. (shrink)
This volume focuses on philosophical problems concerning sense perception in the history of philosophy. It consists of thirteen essays that analyse the philosophical tradition originating in Aristotle’s writings. Each essay tackles a particular problem that tests the limits of Aristotle’s theory of perception and develops it in new directions. The problems discussed range from simultaneous perception to causality in perception, from the representational nature of sense-objects to the role of conscious attention, and from the physical/mental divide to perception as quasi-rational (...) judgement. -/- The volume gives an equal footing to Greek, Arabic, and Latin philosophical traditions. It makes a substantial contribution not just to the study of the Aristotelian analysis of sense perception, but to its reception in the commentary tradition and beyond. Thus, the papers address developments in Alexander of Aphrodisias, Themistius, Avicenna, John of Jandun, Nicole Oresme, and Sayf al-Din al-Amidi, among others. The result of this is a coherent collection that attacks a well-defined topic from a wide range of perspectives and across philosophical traditions. (shrink)
In this paper I discuss what triage is and how it might be applied to the preservation of endangered species. I compare the suggested application oftriage to endangered species with its application to wartime military practice, distribution of food aid, and human population control to show that the situation of endangered species is not analogous to these other suggested uses. I argue that, as far as species preservation is concemed, triage starts with the wrong norms and values: it is “human (...) chauvinistic,” giving primacy to economic, political, and sociocultural aspects that emphasize human interests without recognizing the connection between the survival of other species and the survival of humans. (shrink)
Milner and Goodale have advanced a justly influential theory of the structure of the human visual system. In broad outline, Milner and Goodale hold that the ventral neural pathway is associated with recognition and experiential awareness, and with a kind of indirect control of action. And they hold that, by contrast, the dorsal neural stream is associated with the non-conscious, direct control of visually informed action. Most of the relevant empirical research has focused on the visual control of close-in, “personal (...) space,” reaching and/or grasping. While their view has not escaped controversy and debate, we think that Milner and Goodale have a compelling story to tell about the visual guidance of such close in, “personal space” action. However, the question of whether their scheme applies to behavior with visually specified targets that are outside of the space accessible by simply reaching and grasping is largely unstudied. And it should be studied, since this is the arena of much human behavior. We provide good reason to think that the Milner and Goodale scheme may well not apply to important classes of mid-range, ‘action space’ behavior. But the matter is in the end to be decided in the lab. We describe a research program to do this. (shrink)
In this paper I discuss what triage is and how it might be applied to the preservation of endangered species. I compare the suggested application oftriage to endangered species with its application to wartime military practice, distribution of food aid, and human population control to show that the situation of endangered species is not analogous to these other suggested uses. I argue that, as far as species preservation is concemed, triage starts with the wrong norms and values: it is “human (...) chauvinistic,” giving primacy to economic, political, and sociocultural aspects that emphasize human interests without recognizing the connection between the survival of other species and the survival of humans. (shrink)