Wavelength Theory of Colour Strikes Back: The Return of the Physical

There have been a number of criticisms, based on visual processes, of the Australian view that colour is an objective property of the world. These criticisms have led to subjective theories about colour. These visual processes (metamers, retinex theory, opponent processes, simultaneous contrast, colour constancy, subjective colours) have been examined and it is suggested that they do not carry their supposed critical weight against an objective theory. In particular, it is argued that metamers don't occur in nature and primate colour vision evolved without metamers. Thus normal colour vision occurs without the problem of metamers. This argument, in conjunction with evidence against the critical roles of opponent processes and retinex theory in colour vision, is taken to suggest that colour can be given a photon energy/wavelengthrealism explanation. This proposal allows an account of the many microstructural bases of colour generation put forward by Nassau (1983). It is argued that neither disjunctive realism or reflectance realism are adequate objective explanations of colour.     

Experiential blindness revisited: In defence of a case of embodied cognition

The sensorimotor theory (Noë, 2004, Noë, in press) discusses a special instance of lack of perceptual experience despite no sensory impairment. The phenomenon dubbed “experiential blindness” is cited as evidence for a constitutive relation between sensorimotor skills and perceptual experience. Recently it has been objected (Adams and Aizawa, 2008, Aizawa, 2007) that the cases described by Noë as experiential blindness are cases of pure sensory deficit. This paper argues that while the objections bring out limitations of Noë’s sensorimotor theory they do not do enough to challenge a robust perception–action interdependence claim. There are genuine cases of experiential blindness and these are better explained by the hypothesis of the interdependence of perception and action rather than by a passive vision approach. The cases provide support for a strong thesis of embodied cognition where ongoing sensorimotor dynamics non-trivially constrain perceptual content.     

Late‐ but not early‐onset blindness impairs the development of audio‐haptic multisensory integration

Integrating different senses to reduce sensory uncertainty and increase perceptual precision can have an important compensatory function for individuals with visual impairment and blindness. However, how visual impairment and blindness impact the development of optimal multisensory integration in the remaining senses is currently unknown. Here we first examined how audio‐haptic integration develops and changes across the life span in 92 sighted (blindfolded) individuals between 7 and 70 years of age. We used a child‐friendly task in which participants had to discriminate different object sizes by touching them and/or listening to them. We assessed whether audio‐haptic performance resulted in a reduction of perceptual uncertainty compared to auditory‐only and haptic‐only performance as predicted by maximum‐likelihood estimation model. We then compared how this ability develops in 28 children and adults with different levels of visual experience, focussing on low‐vision individuals and blind individuals that lost their sight at different ages during development. Our results show that in sighted individuals, adult‐like audio‐haptic integration develops around 13–15 years of age, and remains stable until late adulthood. While early‐blind individuals, even at the youngest ages, integrate audio‐haptic information in an optimal fashion, late‐blind individuals do not. Optimal integration in low‐vision individuals follows a similar developmental trajectory as that of sighted individuals. These findings demonstrate that visual experience is not necessary for optimal audio‐haptic integration to emerge, but that consistency of sensory information across development is key for the functional outcome of optimal multisensory integration.     

Why don’t synaesthetic colours adapt away?

Synaesthetes persistently perceive certain stimuli as systematically accompanied by illusory colours, even though they know those colours to be illusory. This appears to contrast with cases where a subject??s colour vision adapts to systematic distortions caused by wearing coloured goggles. Given that each case involves longstanding systematic distortion of colour perception that the subjects recognize as such, how can a theory of colour perception explain the fact that perceptual adaptation occurs in one case but not the other? I argue that these cases and the relationship between them can be made sense of in light of an existing view of colour perception. Understanding colours as ways in which objects and surfaces modify light, perceived through grasping patterns and variations in colour appearances, provides a framework from which the cases and their apparent disanalogy can be predicted and explained. This theory??s ability to accommodate these cases constitutes further empirical evidence in its favour.     

THE MAIN PART AND PILLAR OF BERKELEY'S THEORY: IDEALISM AND PERCEPTUAL HETEROGENEITY

Berkeley subscribed to the principle of heterogeneity, that what we see is qualitatively and numerically different from what we touch. He says of this principle that it is “the main part and pillar of [his] theory.” The argument I present here is that the theory to which Berkeley refers is not just his theory of vision, but what that theory was the preparation for, which is nothing less than his idealism. The argument turns on the passivity of perception, which is what is at stake in the principle of heterogeneity. The author targeted by Berkeley's theory is Descartes, who explicitly denies heterogeneity.     

Reflectance realism and colour constancy: What would count as scientific evidence for hilbert's ontology of colour?

Reflectance realism is an important position in the philosophy of colour. This paper is an examination of David R. Hilbert's case for there being scientific support for the theory. The specific point in question is whether colour science has shown that reflectance is recovered by the human visual system. Following a discussion of possible counter-evidence in the recent scientific literature, I make the argument that conflicting interpretations of the data on reflectance recovery are informed by different theoretical assumptions about the nature of colour, and of perception. If this is so, there cannot be neutral empirical evidence on this point, and this does seem to undermine Hilbert's claim for empirical support. In the end, I suggest alternative ways of thinking about the relationship between colour ontology and empirical work on colour.     

Darwin Puzzled? A Computer-assisted Analysis of Language in the Origin of Species

The aesthetically optimistic view of life in the last paragraph of Darwin’s On the Origin of Species contrasts with the evidence in his autobiography of a supposed perceptive colour blindness to the magnificence of nature. Accepting the theory of evolution as one of the scientific theories that has contributed to disenchantment, my aim is to delve into the Darwinian perception of natural beauty and solve this contrast of perceptions within the framework of the Weberian concept of “disenchantment of the world.” To do this, I have carried out a computer-assisted study of Darwin’s language focusing on the frequency of aesthetic-emotional and religious adjectives and adverbs in the six editions of the Origin. A semantic analysis of the lexicon shows that, although disenchanted, Darwin perceives nature as aesthetically enhanced. I arrive at the conclusion that Darwin’s alleged colour blindness does not come from a loss of his capacity to aesthetically perceive nature, but from his loss of religious belief.

     

Some aspects of explanation in Boškovič

Bo?kovi?'s explanatory procedure and his concept of explanation represents a certain departure from Newton's causal theory and his theory of explanation. Apart from particular elements of causal explanation, Bo?kovi? developed an alternative, non‐causal explanatory strategy. In this paper two different elements of this strategy are discussed: (i) the micro‐reductive explanatory strategy based on Bo?kovi?'s idea of determination, and (ii) a type of explanation of a theory by means of a more general law, through a thought‐experiment. In addition, an outline of the proposed (iii) ‘argument theory’ of explanation in his mature period is made. These aspects are considered with respect to the realist and anti‐realist elements in Bo?kovi?'s epistemology.     

PREFERENTISM AND SELF‐SACRIFICE

According to the argument from self‐sacrifice, standard, unrestricted desire‐based theories of welfare fail because they have the absurd implication that self‐sacrifice is conceptually impossible. I attempt to show that, in fact, the simplest imaginable, completely unrestricted desire‐based theory of well‐being is perfectly compatible with the phenomenon of self‐sacrifice – so long as the theory takes the right form. I go on to consider a new argument from self‐sacrifice against this simple theory, which, I argue, also fails. I conclude that, contrary to popular opinion, considerations of self‐sacrifice do not pose a problem for preferentist theories of welfare.     

Comparison of isokinetic peak force and power in adults with partial and total blindness

For many populations the ability to move efficiently is compromised by an impaired muscular functioning. Strength development is necessary to overcome the effects of gravity to maintain posture and generate movement responses for mobility. The strength and power capabilities of individuals with total blindness (n = 12) were compared to those with partial vision (n = 12) to evaluate effects of vision on performance. Results indicate that (1) no significant differences were apparent between total blindness and partial vision, (2) significant sex differences were evident in each group, and (3) better performance was apparent at lower velocities. It was concluded that physical performance in individuals with blindness and partial vision are equally deficient.     

Keeping it Real: Intentional Inexistents,Fineness‐of‐Grain,and the Dilemma for Extrinsic Higher‐Order Representational Theories

According to the standard argument from targetless higher‐order representations, the possibility of such representations presents a dilemma for higher‐order theorists. In this article I argue that there are two theoretically well‐motivated replies to the standard argument. Consequently, the standard argument against higher‐order theories fails. I then go on to argue that while certain versions of higher‐order theory can adequately respond to the standard argument, they both, nevertheless, fail to explain the fineness‐of‐grain that phenomenally conscious experience appears to have.     

Interventionist Causal Exclusion and Non‐reductive Physicalism

The first part of this paper presents an argument showing that the currently most highly acclaimed interventionist theory of causation, i.e. the one advanced by Woodward, excludes supervening macro properties from having a causal influence on effects of their micro supervenience bases. Moreover, this interventionist exclusion argument is demonstrated to rest on weaker premises than classical exclusion arguments. The second part then discusses a weakening of interventionism that Woodward suggests. This weakened version of interventionism turns out either to be inapplicable to cases of downward causation involving supervening macro properties or to render corresponding causal claims meaningless. In sum, the paper argues that, contrary to what many non‐reductive physicalists claim, interventionism does not render non‐reductive physicalism immune to the problem of causal exclusion.     

The fluttering-heart illusion: a new hypothesis

The fluttering-heart illusion is a perceived lagging behind of a colour target on a background of a different colour when the two are oscillated together. It has been proposed that the illusion is caused by a differential in the perceptual latencies of different colours (Helmholtz 1867/1962), a differential in rod-cone latencies (von Kries 1896) and rod-cone interactions (von Grünau 1975, 1976 Vision Research 15 431-436, 437-440; 16 397-401; see list of references there). The purpose of this experiment was to assess the hypothesis that the fluttering-heart illusion is caused by a differential in the perceived velocities of chromatic and achromatic motion. To evaluate this hypothesis, we tested observers possessing normal colour vision and deuteranopes. The perceived delay of a chromatic target relative to an achromatic target was measured as a function of background cone contrast and target colour. For observers with normal colour vision, the perceived delay of the chromatic target is greater in the L-S than the L-M testing conditions. The reverse is observed in deuteranope observers. We suggest that this is caused by the absence of an L-M opponent mechanism contributing to chromatic motion in deuteranopes. Greater background cone contrasts tended to yield smaller perceived delays in both normal and deuteranope observers, indicating that greater chromatic modulation decreases the perceived delay of the colour target. These results support the hypothesis that the fluttering-heart illusion can be explained by a differential in the perceived velocities of chromatic and achromatic motion.     

Suppression and hypothesis testing: does suppressing stereotypes during interactions help to avoid confirmation biases?

Recent work indicates that trying not to think in stereotypical terms increases the accessibility of stereotypical information, which paradoxically results in more stereotypical judgments. The present study translated the colour‐blindness ideology in general and stereotype suppression research in particular into an hypothesis testing setting. Participants who were asked to suppress their stereotypes when selecting a set of questions were indeed less guided by ambient stereotypes than control participants, thereby showing a reduction of the classical confirmation orientation in question preferences. Still, compared to control participants, suppressors also later reported more polarized impressions such that consistent targets were seen as more stereotypical and inconsistent ones as more counter‐stereotypical. Moreover, group evaluations were more stereotypical for suppressors than for controls indicating that suppression had led to stronger activation of the stereotypical representation. Results are discussed in light of the prevailing belief regarding the benefits of political correctness and colour‐blindness. Copyright © 2003 John Wiley & Sons, Ltd.     

制约国人白内障复明手术的社会因素

全球因白内障致失明者大约2000万人,导致低视力者3倍于此数字,即6000万。手术可使白内障失明者视力恢复正常或有用视力。每年每百万人口接受白内障手术的人数（白内障手术率）是在不同环境中衡量眼保健工作的有用尺度。白内障手术率在各国之间以及一个国家的不同地区都存在极大差异,最高者比利时16000例／百万,2004年统计我...     

Attenuated Change Blindness for Exogenously Attended Items in a Flicker Paradigm

When two scenes are alternately displayed, separated by a mask, even large, repeated changes between the scenes often go unnoticed for surprisingly long durations. Change blindness of this sort is attenuated at “centres of interest” in the scenes, however, supporting a theory of change blindness in which attention is necessary to perceive such changes (Rensink, O'Regan, & Clark, 1997). Problems with this measure of attentional selection - via verbally described “centres of interest” - are discussed, including worries about describability and explanatory impotence. Other forms of attentional selection, not subject to these problems, are employed in a “flicker” experiment to test the attention-based theory of change detection. Attenuated change blindness is observed at attended items when attentional selection is realized via involuntary exogenous capture of visual attention - to late-onset items and colour singletons - even when these manipulations are uncorrelated with the loci of the changes, and are thus irrelevant to the change detection task. These demonstrations ground the attention-based theory of change blindness in a type of attentional selection which is understood more rigorously than are “centres of interest”. At the same time, these results have important implications concerning the nature of exogenous attentional capture.     

Reflexive theories of consciousness and unconscious perception

A core commitment of the reflexive theory of consciousness is that conscious states are themselves necessarily the contents of mental states. The strongest argument for this claim—the necessity of inner-content for consciousness—is the argument from unconscious perception. According to this argument, we find evidence for the necessity claim from cases of alleged unconscious perception, the most well-known and widely discussed of these being blindsight. However, the reflexive theory cannot partake in this argument and therefore, must rely on at least one of the other arguments for the necessity claim. These arguments are significantly less convincing than the argument from unconscious perception, and thus the reflexive theory is left in a dialectically weak position.     

The Effects of Argument Quality and Involvement Type on Attitude Formation and Attitude Change: A Test of Dual‐Process and Social Judgment Predictions

Involvement has long been theoretically specified as a crucial factor determining the persuasive impact of messages. In social judgment theory, ego‐involvement makes people more resistant to persuasion, whereas in dual‐process models, high‐involvement people are susceptible to persuasion when argument quality is high. It is argued that these disparate predictions might be reconciled by either different involvement types (i.e., value relevant vs. outcome relevant) or different attitude modification processes (i.e., attitude change vs. attitude formation). An experiment (N = 684) varying topic, position advocated, outcome relevance, and argument quality tested these moderators. The data were consistent with existence of two different types of involvement, but none of the theoretical predictions were consistent with the data. Instead, a main effect for argument quality had the largest impact on attitude change. Regardless of value‐relevant involvement, outcome‐relevant involvement, and attitude modification process, participants were more persuaded by high‐ rather than low‐quality arguments, with boomerang effects observed for low‐quality arguments. These findings highlight the importance of sound message design in persuasion.