Central to contemporary cognitive science is the notion that mental processes involve computations defined over internal representations. This view stands in sharp contrast to the to visual perception and cognition, whose most prominent proponent has been J.J. Gibson. In the direct theory, perception does not involve computations of any sort; it is the result of the direct pickup of available information. The publication of Gibson's recent book (Gibson 1979) offers an opportunity to examine his approach, and, more generally, (...) to contrast the theory of direct perception with the computational/representational view. In the first part of the present article (Sections 2direct perceptioncase study”: the problem of perceiving the three-dimensional shape of moving objects is examined. This problem, which has been extensively studied within the immediate perception framework, serves to illustrate some of the inherent shortcomings of that approach. Finally, in Section 5, an attempt is made to place the theory of direct perception in perspective by embedding it in a more comprehensive framework. (shrink)

For John Locke, the first step in an investigation of perception should be reflection. Locke's use of the term "perception" is somewhat broad. This chapter first presents a background to Locke's theory, and then describes the general psychophysical principle that governs his approach to sensation and two exceptions to that principle. Next, the chapter elucidates some of the subtleties of Locke's account of the visual perception of shape, subtleties that end up supporting an orthodox interpretation of (...) his answer to the Molyneux question. Some remarks on Locke's account of time perception are then presented. These remarks explain Locke's reasons for thinking that we get the idea of succession and duration from reflection, though he believes that we get ideas of our measures of duration from sensation. Locke infers that we may treat the perception of motion as a useful proxy for thinking about the succession of ideas in our minds. (shrink)

Action is a means of acquiring perceptual information about the environment. Turning around, for example, alters your spatial relations to surrounding objects and, hence, which of their properties you visually perceive. Moving your hand over an object’s surface enables you to feel its shape, temperature, and texture. Sniffing and walking around a room enables you to track down the source of an unpleasant smell. Active or passive movements of the body can also generate useful sources of perceptual information (Gibson (...) 1966, 1979). The pattern of optic flow in the retinal image produced by forward locomotion, for example, contains information about the direction in which you are heading, while motion parallax is a “cue” used by the visual system to estimate the relative distances of objects in your field of view. In these uncontroversial ways and others, perception is instrumentally dependent on action. According to an explanatory framework that Susan Hurley (1998) dubs the “Input-Output Picture”, the dependence of perception on action is purely instrumental: "Movement can alter sensory inputs and so result in different perceptions… changes in output are merely a means to changes in input, on which perception depends directly" (1998: 342). -/- The action-based theories of perception, reviewed in this entry, challenge the Input-Output Picture. They maintain that perception can also depend in a noninstrumental or constitutive way on action (or, more generally, on capacities for object-directed motor control). This position has taken many different forms in the history of philosophy and psychology. Most action-based theories of perception in the last 300 years, however, have looked to action in order to explain how vision, in particular, acquires either all or some of its spatial representational content. Accordingly, these are the theories on which we shall focus here. -/- We begin in Section 1 by discussing George Berkeley’s Towards a New Theory of Vision (1709), the historical locus classicus of action-based theories of perception, and one of the most influential texts on vision ever written. Berkeley argues that the basic or “proper” deliverance of vision is not an arrangement of voluminous objects in three-dimensional space, but rather a two-dimensional manifold of light and color. We then turn to a discussion of Lotze, Helmholtz, and the local sign doctrine. The “local signs” were felt cues for the mind to know what sort of spatial content to imbue visual experience with. For Lotze, these cues were “inflowing” kinaesthetic feelings that result from actually moving the eyes, while, for Helmholtz, they were “outflowing” motor commands sent to move the eyes. -/- In Section 2, we discuss sensorimotor contingency theories, which became prominent in the 20thcentury. These views maintain that an ability to predict the sensory consequences of self-initiated actions is necessary for perception. Among the motivations for this family of theories is the problem of visual direction constancy—why do objects appear to be stationary even though the locations on the retina to which they reflect light change with every eye movement?—as well as experiments on adaptation to optical rearrangement devices (ORDs) and sensory substitution. -/- Section 3 examines two other important 20th century theories. According to what we shall call the motor component theory, efference copies generated in the oculomotor system and/or proprioceptive feedback from eye-movements are used together with incoming sensory inputs to determine the spatial attributes of perceived objects. Efferent readiness theories, by contrast, look to the particular ways in which perceptual states prepare the observer to move and act in relation to the environment. The modest readiness theory, as we shall call it, claims that the way an object’s spatial attributes are represented in visual experience can be modulated by one or another form of covert action planning. The bold readiness theory argues for the stronger claim that perception just is covert readiness for action. -/- In Section 4, we move to the disposition theory, most influentially articulated by Gareth Evans (1982, 1985), but more recently defended by Rick Grush (2000, 2007). Evans’ theory is, at its core, very similar to the bold efferent readiness theory. There are some notable differences, though. Evans’ account is more finely articulated in some philosophical respects. It also does not posit a reduction of perception to behavioral dispositions, but rather posits that certain complicated relations between perceptual input and behavioral provide spatial content. Grush proposes a very specific theory that is like Evans’ in that it does not posit a reduction, but unlike Evans’ view, does not put behavioral dispositions and sensory input on an undifferentiated footing. (shrink)

In this article, I analyze the particular perception of the world Baptists start to learn during their conversion which I call the three-dimensional perception of reality. This concept refers to the ability to incorporate narratives from the Bible into everyday life events and interpret both personal stories and world events accordingly, thereby making the Bible ever relevant. Based on ethnographic fieldwork, I show how events from the believers' daily lives are perceived and explained in the light of biblical (...) stories. Regardless of the fact that the two are separated in time and in space, the biblical story is still seen as a proto-event to the current one. No matter how diverse the believers' experiences, they are capable of finding an equivalent episode in the Bible. The scripture, therefore, is ever present in the believers' lives, as a source of meaning and interpretation. (shrink)

Psychology and philosophy have long reflected on the role of perspective in vision. Since the dawn of modern vision science—roughly, since Helmholtz in the late 1800s—scientific explanations in vision have focused on understanding the computations that transform the sensed retinal image into percepts of the three-dimensional environment. The standard view in the science is that distal properties—viewpoint-independent properties of the environment (object shape) and viewpoint-dependent relational properties (3D orientation relative to the viewer)–are perceptually represented and that properties of the (...) proximal stimulus (in vision, the retinal image) are not. This view is woven into the nature of scientific explanation in perceptual psychology, and has guided impressive advances over the past 150 years. A recently published article suggests that in shape-perception, the standard view must be revised. It argues, on the basis of new empirical data, that a new entity—perspectival shape—should be introduced into scientific explanations of shape perception. Specifically, the article’s centrally advertised claim is that, in addition to distal shape, perspectival shape is perceived. We argue that this claim rests on a series of mistakes. Problems in experimental design entail that the article provides no empirical support for any claims regarding either perspective or the perception of shape. There are further problems in scientific reasoning and conceptual development. Detailing these criticisms and explaining how science treats these issues is meant to clarify method and theory, and to improve exchanges between the science and philosophy of perception. (shrink)

Arguably the most foundational principle in perception research is that our experience of the world goes beyond the retinal image; we perceive the distal environment itself, not the proximal stimulation it causes. Shape may be the paradigm case of such “unconscious inference”: When a coin is rotated in depth, we infer the circular object it truly is, discarding the perspectival ellipse projected on our eyes. But is this really the fate of such perspectival shapes? Or does a tilted (...) coin retain an elliptical appearance even when we know it’s circular? This question has generated heated debate from Locke and Hume to the present; but whereas extant arguments rely primarily on introspection, this problem is also open to empirical test. If tilted coins bear a representational similarity to elliptical objects, then a circular coin should, when rotated, impair search for a distal ellipse. Here, nine experiments demonstrate that this is so, suggesting that perspectival shapes persist in the mind far longer than traditionally assumed. Subjects saw search arrays of three-dimensional “coins,” and simply had to locate a distally elliptical coin. Surprisingly, rotated circular coins slowed search for elliptical targets, even when subjects clearly knew the rotated coins were circular. This pattern arose with static and dynamic cues, couldn’t be explained by strategic responding or unfamiliarity, generalized across shape classes, and occurred even with sustained viewing. Finally, these effects extended beyond artificial displays to real-world objects viewed in naturalistic, full-cue conditions. We conclude that objects have a remarkably persistent dual character: their objective shape “out there,” and their perspectival shape “from here.”. (shrink)

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

The paper addresses the capabilities and limitations of extrafoveal processing during a categorical visual search. Previous research has established that a target could be identified from the very first or without any saccade, suggesting that extrafoveal perception is necessarily involved. However, the limits in complexity defining the processed information are still not clear. We performed four experiments with a gradual increase of stimuli complexity to determine the role of extrafoveal processing in searching for the categorically defined geometric shape. (...) The series of experiments demonstrated a significant role of extrafoveal processing while searching for simple two‐dimensional shapes and its gradual decrease in a condition with more complicated three‐dimensional shapes. The factors of objects’ spatial orientation and distractor homogeneity significantly influenced both reaction time and the number of saccades required to identify a categorically defined target. An analysis of the individual p‐value distributions revealed pronounced individual differences in using extrafoveal analysis and allowed examination of the performance of each particular participant. The condition with the forced prohibition of eye movements enabled us to investigate the efficacy of covert attention in the condition with complicated shapes. Our results indicate that both foveal and extrafoveal processing are simultaneously involved during a categorical search, and the specificity of their interaction is determined by the spatial orientation of objects, type of distractors, the prohibition to use overt attention, and individual characteristics of the participants. (shrink)

How much is given in perceptual experience, and how much must be constructed? John Locke's answer to this question contains two prima facie incompatible strands. On the one hand, he claims that ideas of primary qualities come to us passively, through multiple senses: the idea of a sphere can be received either by sight or touch. On the other hand, Locke seemingly thinks that a faculty he calls “judgment” is needed to create visual ideas of three‐dimensional shapes. How can (...) these accounts be made consistent? The problem comes to a head in the discussion of Molyneux's problem: can a person born blind and then made to see identify a sphere and a cube, when he had only touched them in the past? Locke's answer is no, but, as George Berkeley points out, it is hard to see why: if the ideas of shapes come to us through sight as well as touch, nothing should stop Molyneux man from instantly recognizing sphere and cube. Pace much of the existing literature, I argue that although Locke does think we receive visual ideas of primary qualities, the faculty of judgment is required to “inflate” those ideas into three dimensions and to correct for other perspectival distortions. I then show how this answer is consistent with the rest of his theory of perception. (shrink)

Previous theories of early vision have assumed that visual search is based on simple two-dimensional aspects of an image, such as the orientation of edges and lines. It is shown here that search can also be based on three-dimensional orientation of objects in the corresponding scene, provided that these objects are simple convex blocks. Direct comparison shows that image-based and scene-based orientation are similar in their ability to facilitate search. These findings support the hypothesis that scene-based properties are represented at (...) preattentive levels in early vision. (shrink)

Corruption involves greed, money, and risky decision-making. We explore the love of money, pay satisfaction, probability of risk, and dishonesty across cultures. Avaricious monetary aspiration breeds unethicality. Prospect theory frames decisions in the gains-losses domain and high-low probability. Pay dissatisfaction (in the losses domain) incites dishonesty in the name of justice at the individual level. The Corruption Perceptions Index, CPI, signals a high-low probability of getting caught for dishonesty at the country level. We theorize that decision-makers adopt avaricious love-of-money aspiration (...) as a lens and frame dishonesty in the gains-losses domain (pay satisfaction-dissatisfaction, Level 1) and high-low probability (CPI, Level 2) to maximize expected utility and ultimate serenity. We challenge the myth: Pay satisfaction mitigates dishonesty across nations consistently. Based on 6500 managers in 32 countries, our cross-level three-dimensional visualization offers the following discoveries. Under high aspiration conditions, pay dissatisfaction excites the highest- (third-highest) avaricious justice-seeking dishonesty in high (medium) CPI nations, supporting the certainty effect. However, pay satisfaction provokes the second-highest avaricious opportunity-seizing dishonesty in low CPI entities, sustaining the possibility effect—maximizing expected utility. Under low aspiration conditions, high pay satisfaction consistently leads to low dishonesty, demonstrating risk aversion—achieving ultimate serenity. We expand prospect theory from a micro and individual-level theory to a cross-level theory of monetary wisdom across 32 nations. We enhance the S-shaped Curve to three 3-D corruption surfaces across three levels of the global economic pyramid, providing novel insights into behavioral economics, business ethics, the environment, and responsibility. (shrink)

Certain features of perception – the quale red, for example, and other qualia – must be regarded as additions to the materialist neurophysiological picture of perception. The perception of three-dimensional volumetric objects can also be seen as qualitative additions to the neurophysiological processes in the brain, possibly without additions to the information content.

It has generally been assumed that rapid visual search is based on simple features and that spatial relations between features are irrelevant for this task. Seven experiments involving search for line drawings contradict this assumption; a major determinant of search is the presence of line junctions. Arrow- and Y-junctions were detected rapidly in isolation and when they were embedded in drawings of rectangular polyhedra. Search for T-junctions was considerably slower. Drawings containing T-junctions often gave rise to very slow search even (...) when distinguishing arrow- or Y-junctions were present. This sensitivity to line relations suggests that preattentive processes can extract 3-dimensional orientation from line drawings. A computational model is outlined for how this may be accomplished in early human vision. (shrink)

I want to differentiate between two very different ways of organizing pictorial elements at a very abstract level: -/- (2D) two-dimensionally: pictorial elements are organized and grouped according to their outline shape on the picture surface and (3D) three-dimensionally: pictorial elements are organized and grouped according to their position in the depicted space. -/- Suppose you need to depict seven identical spheres. On the most general level, there are two ways of doing this: you can arrange the seven spheres (...) in space and then choose a vantage point in this space from which you want to depict them. Or you can arrange seven circles (the outline shapes of the seven spheres) on the two-dimensional surface of the picture. The former method is an instance of three-dimensional pictorial organization, whereas the latter one is an instance of two-dimensional pictorial organization. (shrink)

Are shapes of objects intrinsic to them? The issue has been intensely debated. Special relativity (SR) adds a new dimension to it by relativizing three-dimensional (3D) shapes not just to times, but to times-in-frames. Arguably, however, such relativized spatial shapes are mere perspectival representations of an invariant, hence intrinsic, four-dimensional (4D) shape of an object in Minkowski spacetime. In a recent note, Matthew Davidson questions the intrinsicality of 4D shapes in SR. I show that his conclusion and the reasoning (...) behind it are in error. (shrink)

Very encouraging results have been obtained from a new program that derives a dense three-dimensional evidence grid representation of a robot's surroundings from wide-angle stereoscopic images. The pro gram adds several spatial rays of evidence to a grid for each of about 2,500 local image features chosen per stereo pair. It was used to construct a 256x256x64 grid, representing 6 by 6 by 2 meters, from a hand- collected test set of twenty stereo image pairs of an office scene. Fifty (...) nine stereo pairs of an 8 by 8 meter laboratory were also processed. The positive (probably occupied) cells of the grids, viewed in perspec tive, resemble dollhouse scenes. Details as small as the curvature of chair armrests are discernible. The processing time, on a 100 MIPS Sparc 20, is less than five seconds per stereo pair, and total memory is under 16 megabytes. The results seem abundantly adequate for very reliable navigation of freely roaming mobile robots, and plausibly adequate for shape identification of objects bigger than 10 centimeters. The program is a first proof of concept, and awaits optimizations, enhancements, variations, extensions and applications. (shrink)

This book deals with philosophical aspects regarding the perception of spatial relationships in two and three-dimensional art. It provides a structural understanding of how art is perceived within the space created by the artwork, and employs a mapping sentence and partial order mereology to model perceptual structure. It reviews the writing of philosophers such as Paul Crowther and art theorists such as Krauss to establish the need for this research. The ontological model established Paul Crowther is used to guide (...) an interactive account of his ontology in the interpretations of the perceptual process of three-dimensional abstract art to allow the formulation of a more comprehensive philosophical account. The book uniquely combines structuralist and post-structuralist approaches to artistic perception and understanding with a conceptual structure from facet theory, which is clarified with the help of a mapping sentence and partial order mereology. (shrink)

The present study collected a larger set of three-dimensional data on human crania from the Kofun period (as well as from previous periods, i.e., the Jomon and Yayoi periods) in the Japanese archipelago (AD 250 to around 700) than previous studies. Three-dimensional geometric morphometrics were employed to investigate human migration patterns in finer-grained phases. These results are consistent with those of previous studies, although some new patterns were discovered. These patterns were interpreted in terms of demic diffusion, archaeological findings, and (...) historical evidence. In particular, the present results suggest the presence of a gradual geological cline throughout the Kofun period, although the middle period did not display such a cline. This discrepancy might reflect social changes in the middle Kofun period, such as the construction of keyhole-shaped mounds in the peripheral regions. The present study implies that a broader investigation with a larger sample of human crania is essential to elucidating macro-level cultural evolutionary processes. (shrink)

Victor Vasarely's (1906–1997) important legacy to the study of human perception is brought to the forefront and discussed. A large part of his impressive work conveys the appearance of striking three-dimensional shapes and structures in a large-scale pictorial plane. Current perception science explains such effects by invoking brain mechanisms for the processing of monocular (2D) depth cues. Here in this study, we illustrate and explain local effects of 2D color and contrast cues on the perceptual organization in terms (...) of figure-ground assignments, i.e. which local surfaces are likely to be seen as “nearer” or “bigger” in the image plane. Paired configurations are embedded in a larger, structurally ambivalent pictorial context inspired by some of Vasarely's creations. The figure-ground effects these configurations produce reveal a significant correlation between perceptual solutions for “nearer” and “bigger” when other geometric depth cues are missing. In consistency with previous findings on similar, albeit simpler visual displays, a specific color may compete with luminance contrast to resolve the planar ambiguity of a complex pattern context at a critical point in the hierarchical resolution of figure-ground uncertainty. The potential role of color temperature in this process is brought forward here. Vasarely intuitively understood and successfully exploited the subtle context effects accounted for in this paper, well before empirical investigation had set out to study and explain them in terms of information processing by the visual brain. (shrink)

People can represent temporal stimuli (e.g., pictures depicting past and future events) as spatially connoted dimensions arranged along the three main axes (horizontal, sagittal, and vertical). For example, past and future events are generally represented, from the perspective of the individuals, as being placed behind and in front of them, respectively. Here, we report that such a 3D representation can also emerge for facial stimuli of different ages. In three experiments, participants classified a central target face, representing an individual at (...) different age stages, as younger or older than the reference face of 40 years. Manual responses were provided with two keys placed along the horizontal axis (Experiment 1), the sagittal axis (Experiment 2), and the vertical axis (Experiment 3). The results indicated that the younger faces were represented on the left/back/top side of the space, whereas the older faces were represented on the right/forward/bottom side of the space. Furthermore, in all experiments, the latencies decreased with the absolute difference between the age of the target face and that of the reference face (i.e., a distance effect). Overall, this work suggests that the spatial representation of time includes social features of the human face. (shrink)

Visualizing and mental imagery are thought to be cognitive states by all sides of the imagery debate. Yet the phenomenology of those states has distinctly visual ingredients. This has potential consequences for the hypothesis that vision is cognitively impenetrable, the ability of visual processes to ground perceptual warrant and justification, and the distinction between cognitive and perceptual phenomenology. I explore those consequences by describing two forms of visual ambiguity that involve visualizing: the ability to visually experience a picture surface as (...) flat after it has caused volumetric nonconceptual contents, and the ability to use a surface initially perceived as flat to visualize three-dimensional scenes. In both cases, the visual processes which extract viewer-centered volumetric shapes have to rely solely on monocular depth cues in the absence of parallax and stereopsis. Those processes can be cognitively penetrated by acts of visualizing, including ones that draw on conceptual information about kinds. However, the penetrability of the visual processes does not weaken their ability to provide perceptual warrant and justification for beliefs. The reason is that picture perceptions—whether they are stimulus -driven or based on acts of visualizing—are different to object perceptions both phenomenologically and in terms of their functional roles as states. Thus, although the penetrability of the visual processes does mean that subjects can have visual experiences with contradictory contents, perceptual belief is adopted at most towards one set of contents, and questions of warrant and justification are raised only for those contents. A rule-proving exception is provided by trompe-l’oeils. (shrink)

Recent research investigating the language–thought interface in the spatial domain points to representations of the horizontal and vertical dimensions that closely resemble those posited by Jeffery et al. However, the findings suggest that such representations, rather than being tied to navigation, may instead reflect more general properties of the perception of space.

This paper examined three approaches for understanding perceptions of ethics: moral philosophies, cognitive moral development, and ethical value systems. First, the dimensionality of the moral philosophy approach was examined. Next, an attempt was made to integrate the models. Finally, each of the model's various components were used in a regression equation to isolate the best predictors of ethicality. Results indicated that the moral philosophies can be considered distinct entities, but the common underlying theme between the approaches was not as predicted. (...) Also, individuals used a variety of approaches, not always the same ones, to determine the ethicalness of situations. (shrink)

The universality, invariance, and elegance of principles governing the universe may be reflected in principles of the minds that have evolved in that universe – provided that the mental principles are formulated with respect to the abstract spaces appropriate for the representation of biologically significant objects and their properties. (1) Positions and motions of objects conserve their shapes in the geometrically fullest and simplest way when represented as points and connecting geodesic paths in the six-dimensional manifold jointly determined by the (...) Euclidean group of three-dimensional space and the symmetry group of each object. (2) Colors of objects attain constancy when represented as points in a three-dimensional vector space in which each variation in natural illumination is canceled by application of its inverse from the three-dimensional linear group of terrestrial transformations of the invariant solar source. (3) Kinds of objects support optimal generalization and categorization when represented, in an evolutionarily-shaped space of possible objects, as connected regions with associated weights determined by Bayesian revision of maximum-entropy priors. Key Words: apparent motion; Bayesian inference; cognition; color constancy; generalization; mental rotation; perception; psychological laws; psychological space; universal laws. (shrink)

Neuroarchitecture uses neuroscientific tools to better understand architectural design and its impact on human perception and subjective experience. The form or shape of the built environment is fundamental to architectural design, but not many studies have shown the impact of different forms on the inhabitants’ emotions. This study investigated the neurophysiological correlates of different interior forms on the perceivers’ affective state and the accompanying brain activity. To understand the impact of naturalistic three-dimensional (3D) architectural forms, it is essential (...) to perceive forms from different perspectives. We computed clusters of form features extracted from pictures of residential interiors and constructed exemplary 3D room models based on and representing different formal clusters. To investigate human brain activity during three-dimensional perception of architectural spaces, we used a mobile brain/body imaging (MoBI) approach recording the electroencephalogram (EEG) of participants while they naturally walk through different interior forms in virtual reality (VR). The results revealed a strong impact of curvature geometries on activity in the anterior cingulate cortex (ACC). Theta band activity in ACC correlated with specific feature types (rs (14) = 0.525, p = 0.037) and geometry (rs (14) = - 0.579, p = 0.019), providing evidence for a role of this structure in processing architectural features beyond their emotional impact. The posterior cingulate cortex and the occipital lobe were involved in the perception of different room perspectives during the stroll through the rooms. This study sheds new light on the use of mobile EEG and VR in architectural studies and provides the opportunity to study human brain dynamics in participants that actively explore and realistically experience architectural spaces. (shrink)

This article seeks the origin, in the theories of Ibn al-Haytham (Alhazen), Descartes, and Berkeley, of two-stage theories of spatial perception, which hold that visual perception involves both an immediate representation of the proximal stimulus in a two-dimensional ‘‘sensory core’’ and also a subsequent perception of the three dimensional world. The works of Ibn al-Haytham, Descartes, and Berkeley already frame the major theoretical options that guided visual theory into the twentieth century. The field of visual perception (...) was the first area of what we now call psychology to apply mathematics, through geometrical models as used by Euclid, Ptolemy, Ibn al-Haytham, and Descartes (among others). The article shows that Kepler’s discovery of the retinal image, which revolutionized visual anatomy and entailed fundamental changes in visual physiology, did not alter the basic structure of theories of spatial vision. These changes in visual physiology are advanced especially in Descartes' Dioptrics and his L'Homme. Berkeley develops a radically empirist theory vision, according to which visual perception of depth is learned through associative processes that rely on the sense of touch. But Descartes and Berkeley share the assertion that there is a two-dimensional sensory core that is in principle available to consciousness. They also share the observation that we don't usually perceived this core, but find depth and distance to be phenomenally immediate, a point they struggle to accommodate theoretically. If our interpretation is correct, it was not a change in the theory of the psychology of vision that engendered the idea of a sensory core, but rather the introduction of the theory into a new metaphysical context. (shrink)

Research in communication studies has suggested that Al-Jazeera produces different versions of news stories for different audiences. Yet, examining the linguistic means used to create these versions has remained under-researched. Drawing on Fairclough’s three-dimensional model (1992) and Halliday’s Transitivity Model (1985), this study aims at exploring how Al-Jazeera Arabic (AJA) and Al-Jazeera English (AJE) discursively represented the participants involved in the 2022 Russo-Ukrainian conflict in headlines. The analysis of transitivity patterns in AJA and AJE headlines reveals both similar and different (...) representations of the conflict. Although they avoided negative labeling of the Russian government, both channels ascribed conflict escalation to it, highlighting civilians suffering and protesting. Nevertheless, while AJE emphasized the Ukrainian government vulnerability, AJA presented the conflict as a confrontation between two symmetrical forces. Similarities are attributed to organizational and social institutional forces, while differences result from different editorial policies and audience preferences. As discursive and social practices, the headlines contribute to shaping audience perceptions of the conflict, with AJA challenging the prevailing western narrative of the conflict while AJE reinforcing it. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Russell's external world: 1912-1921 by Ronald E. Nusenoff IN "The Relation of Sense-data to Physics",lOur Knowledge ofthe External World,2 and "The Ultimate Constituents ofMatter",3 Russell presents a phenomenalistic reduction ofphysical objects. On this theory, the external world becomes a physical space of six dimensions, which must be logically constructed by a three-dimensional ordering of three-dimensional phenomenal spaces. In what follows, we will consider Russell's varying views, from causal realism (...) in The Problems of Philosophy,4 through phenomenalism, to neutral monism in The Analysis ofMind,5 on the nature ofthe external world. We will pay particular attention to the relation between physical and phenomenal space, and the status ofthe causal theory ofperception. 1. Realism (1912) In The Problems ofPhilosophy, Russell distinguishes a single "real" space ofscience from the "apparent" spaces ofperception. He begins with various cases of perceptual relativity, illusion, etc., and from these infers that those object which are immediately known to us are not the physical objects which the layman might take them to be. Rather, what are immediately known are sense-data, these being caused by, and so in some sense "corresponding" to, physical obI "The Relation of Sense-data to Physics", Scientia, 4 (1914), reprinted as Chapter VIII of Mysticism and Logic and Other Essays (London, 1918). 2 Our Knowledge ofthe External World as a Fieldfor Scientific Method in Philosophy (London, 1914). 3 "The Ultimate Constituents of Matter", Monist, 25 (1915), reprinted as Chapter VII of Mysticism and Logic. 4 The Problems ofPhilosophy (London, 1946 [lst published, 1912]). 5 The Analysis of Mind (London, 1921). 65 66 Russell, nos. 29-32 (1978) jects. Physical objects are located in "one public all-embracing physical space", while "our sense-data are situated in our private spaces, either the space of sight or the space of touch or such vaguer spaces as other senses may give us".6 Through experience, we are able to correlate these various private sense-data spaces (i.e., in so far as we can correlate experiences in one with experiences in another). What Russell does not go on to do here is define physical space in terms of private spaces. Given that (a) Space is relational rather than absolute, and (b) All that we can know about physical objects is that both they and their relations "correspond" to our sense-data and their relations, then (c) "we may assume that there is a physical space in which physical objects have spatial relations corresponding to those which the corresponding sense-data have in our private spaces".7 Our knowledge of physical space is then merely knowledge of relative position, and other features, e.g., shape, are "only supposed to correspond to the physical space so far as is required for the preservation of the order".8 On this view, the existence ofa physical space is necessitated solely by, and so is no more plausible than, the need for physcial objects. Russell's argument for accepting our "instinctive" belief that physical objects exist is less than compelling. Since this belief does not lead to any difficulties, but on the contrary tends to simplify and systemize our account of our experiences, there seems no good reason for rejecting it.9 In what follows, ~e shall see that Russell's phenomenalism is not explainable as differing from the realism found in The Problems of Philosophy merely in the rejection of this "instinctive" belief. II. Phenomenalism (1914-?) In his "Reply to Criticisms" in the Schilpp collection,IO Russell seems to deny that he ever really accepted phenomenalism. 6 The Problems of Philosophy, pp. 30-1 7 Ibid., p. 31. 8 Ibid., p. 33. 9Ibid., p. 24. 10"Reply to Criticisms", in P.A. Schilpp (ed.), The Philosophy ofBertrand Russell (Evanston and Chicago, 1944), pp. 679-741. Russell's external world 67 Mr. Boodin quotes a passage from me according to which it appears that at a certain time I thought only percepts were real. This was a technical hypothesis which I was trying to make logically adequate. II However, only a few pages earlier he had remarked: There are some who would deny that physics need say anything about what cannot... (shrink)

The question of the dimensionality of space has informed the development of physics since the beginning of the twentieth century in the quest for a unified picture of quantum processes and gravitation. Scientists have worked within various approaches to explain why the universe appears to have a certain number of spatial dimensions. The question of why space has three dimensions has a genuinely philosophical nature that can be shaped as a problem of justifying a contingent necessity of the world. In (...) contrast to explanations of three-dimensionality based on anthropic arguments, we support the search for a theory that provides a justification for the dimensionality of space based on a combination of deductive and inductive reasoning applied to science. In doing so, we argue that Kant correctly approached the question in “Thoughts on the true estimation of living forces” by connecting space dimensionality and the inverse square law. In expounding the strategy of Kant’s argument, we describe the main features of a general Kantian explanation of the dimensionality of space and discuss them with respect to current accounts of explanation in the philosophy of science, such as inference to the best explanation and the deductive-nomological model. (shrink)

There have recently been various empirical attempts to answer Molyneux’s question, for example, the experiments undertaken by the Held group. These studies, though intricate, have encountered some objections, for instance, from Schwenkler, who proposes two ways of improving the experiments. One is “to re-run [the] experiment with the stimulus objects made to move, and/or the subjects moved or permitted to move with respect to them” (p. 94), which would promote three dimensional or otherwise viewpoint-invariant representations. The other is “to use (...) geometrically simpler shapes, such as the cube and sphere in Molyneux’s original proposal, or planar figures instead of three-dimensional solids” (p. 188). Connolly argues against the first modification but agrees with the second. In this article, I argue that the second modification is also problematic (though still surmountable), and that both Schwenkler and Connolly are too optimistic about the prospect of addressing Molyneux’s question empirically. (shrink)

In a backward masking paradigm Epstein, Hatfield, and Muise (1977) found that presentation of a frontoparallel pattern mask caused the perceived shape of elliptical figures which were rotated in depth to conform to a projective shape function. The current study extended the masking function by examining the effect of a mask which was partially or wholly cotemporal with the target. The study also assessed the functional equivalence of the masking treatment and the conventional treatment for minimizing depth information. (...) Reports of perceived shape and perceived orientation were obtained under three conditions: binocular without mask, binocular with mask, monocular without mask. Under the first condition, perceived shape conformed to objective shape and perceived orientation was proportional to objective orientation. Under the latter two conditions, perceived shape was in very close agreement to projective shape and the two functions did not differ. Orientation was underestimated greatly under both conditions. We concluded that the effect of the mask on perceived shape is mediated by its effect on encoding of orientation information, although an additional effect on the subsequent stage of shape-slant integration cannot be excluded. (shrink)

Schwenkler (2012) criticizes a 2011 experiment by R. Held and colleagues purporting to answer Molyneux’s question. Schwenkler proposes two ways to re-run the original experiment: either by allowing subjects to move around the stimuli, or by simplifying the stimuli to planar objects rather than three-dimensional ones. In Schwenkler (2013) he expands on and defends the former. I argue that this way of re-running the experiment is flawed, since it relies on a questionable assumption that newly sighted subjects will be able (...) to appreciate depth cues. I then argue that the second way of re-running the experiment is successful both in avoiding the flaw of original Held experiment, and in avoiding the problem with the first way of re-running the experiment. (shrink)

Shape and slant judgments of rotated or frontoparallel ellipses were elicited from three groups of 10 subjects. A masking stimulus was introduced to control processing time. Backward masking trials were presented with interstimulus intervals of 0, 25, and 50 msec, Reduction of processing time altered shape judgments in the direction of projective shape and slant judgments in the direction of frontoparallelness. This finding is consistent with the shape-slant invariance hypothesis. In order to study the effects of (...) processing load, one group of subjects was given prior knowledge of the kind of judgment to be made on each trial, one group had no prior knowledge, and a third group made both judgments on each trial. The effects of the processing load manipulation were interpreted in terms of the role of attention in perceptual encoding. Consistent with previous findings, allocation of attention did not affect perceptual encoding. (shrink)

When we perceive an object, we perceive the object from a perspective. As a consequence of the perspectival nature of perception, when we perceive, say, a circular coin from different angles, there is a respect in which the coin looks circular throughout, but also a respect in which the coin's appearance changes. More generally, perception of shape and size properties has both a constant aspect—an aspect that remains stable across changes in perspective—and a perspectival aspect—an aspect that (...) changes depending on one's perspective on the object. How should we account for the perspectival aspect of spatial perception? We present a framework within which to discuss the perspectival aspect of perception and put forward three desiderata that any account of the perspectival aspect of perception should satisfy. We discuss views on which the perspectival aspect of perception is analyzed in terms of constitutively mind-dependent appearance properties as well as views on which the perspectival aspect of perception is analyzed in terms of representations of mind-independent perspectival properties. (shrink)

How does perceptual learning take place early in life? Traditionally, researchers have focused on how infants make use of information within displays to organize it, but recently, increasing attention has been paid to the question of how infants perceive objects differently depending upon their recent interactions with the objects. This experiment investigates 10-month-old infants' use of brief prior experiences with objects to visually organize a display consisting of multiple geometrically shaped three-dimensional blocks created for this study. After a brief exposure (...) to a multipart portion of the display, each infant was shown two test events, one of which preserved the unit the infant had seen and the other of which broke that unit. Overall, infants looked longer at the event that broke the unit they had seen prior to testing than the event that preserved that unit, suggesting that infants made use of the brief prior experience to (a) form a cohesive unit of the multipart portion of the display they saw prior to test and (b) segregate this unit from the rest of the test display. This suggests that infants made inferences about novel parts of the test display based on limited exposure to a subset of the test display. Like adults, infants learn features of the three-dimensional world through their experiences in it. (shrink)

Magnetoencephalography (MEG) and electroencephalography (EEG) are invaluable neuroscientific tools for unveiling human neural dynamics in three dimensions (space, time, and frequency), which are associated with a wide variety of perceptions, cognition, and actions. MEG/EEG also provides different categories of neuronal indices including activity magnitude, connectivity, and network properties along the three dimensions. In the last 20 years, interest has increased in inter-regional connectivity and complex network properties assessed by various sophisticated scientific analyses. We herein review the definition, computation, short history, (...) and pros and cons of connectivity and complex network (graph-theory) analyses applied to MEG/EEG signals. We briefly describe recent developments in source reconstruction algorithms essential for source-space connectivity and network analyses. Furthermore, we discuss a relatively novel approach used in MEG/EEG studies to examine the complex dynamics represented by human brain activity. The correct and effective use of these neuronal metrics provides a new insight into the multi-dimensional dynamics of the neural representations of various functions in the complex human brain. (shrink)

In De Anima II.6, Aristotle divides the objects of perception into three kinds: “special perceptibles" (idia aisthêta) such as colours, sounds and flavours, which can be perceived in their own right by only one sense; “common perceptibles" (koina aisthêta) such as shapes, sizes and movements, which can be perceived in their own right by multiple senses; and “incidental perceptibles,” such as the son of Diares, which can be perceived only “incidentally” (kata sumbebêkos). In this paper, I examine this division (...) of perceptibles and consider what it amounts to. First, I argue that Aristotle’s distinction between perceiving something in its own right (kath' hauto) and perceiving it incidentally marks a causal distinction: what is perceived in its own right causes perception as such, whereas what is perceived incidentally coincides with what is perceived in its own right. Second, I argue that for Aristotle special perceptibles, unlike common perceptibles, belong to homogeneous bodies on account of their chemical composition. Finally, I explain the primacy Aristotle assigns to special perceptibles and his claim that perception of them alone is free from error. I conclude with some brief remarks on Aristotle and the primary/secondary quality distinction. (shrink)

Our visual experience of the world is one of diverse objects and events, each with particular colors, shapes, and motions. This experience is so coherent, so immediate, and so effortless that it seems to result from a single system that lets us experience everything in our field of view. But however appealing, this belief is mistaken: there are severe limits on what can be visually experienced. -/- For example, in a display for air-traffic control it is important to track all (...) moving items. For a single item, this can be done without problem. Three or four can also be tracked, although some degree of effort may be needed. As the number is increased further, accurate tracking becomes more and more difficult—and eventually, impossible. Performance is evidently affected by a factor within the observer which enables certain kinds of perception to occur, but is limited in some way. This factor is generally referred to as attention. -/- At various times, attention has been associated with clarity of perception, intensity of perception, consciousness, selection, or the allocation of a limited “resource” enabling various operations (see Hatfield, 1998). During the past several decades, considerable progress has been achieved by focusing on the idea of selection (Broadbent, 1982). In particular, attention can be productively viewed as contingently selective processing. This can be embodied in various ways by various processes—there need not be a single quantity identified with all forms of attention, or a single site where it operates (Allport, 1993; Tsotsos, 2011). Although “paying attention” is often considered to be a unitary operation, it may simply refer to the control of one or more selective processes, ideally in a co-ordinated way. While this view has some cost in terms of conceptual simplicity, it can help make sense of a large set of phenomena. -/- This article surveys several of the major issues in our understanding of attention and how it relates to perception. It focuses on vision, since many—if not all—considerations are similar for all sensory modalities, and the level of understanding achieved in this domain is currently the most advanced. (shrink)