Seeing happens effortlessly and yet is endlessly complex. Among the most fascinating aspects of visual perception is its stability and constancy. As we shift our gaze or move about the world, the light projected onto the retinas is constantly changing. Yet the surrounding objects appear stable in their properties. Psychologists have long been interested in the constancies. They have asked questions such as: How good is constancy? Is constancy a fact about how things look, or is it (...) a product of our beliefs and judgments about how things look? How can the contents of visual experience be studied experimentally? Philosophers have long been interested in characterizing visual experience and have become widely interested in the constancies more recently. As psychologists and philosophers have interacted, new questions have arisen: If experience is not as of retinal stimulation (proximal mode), but does not always exhibit constancy (or at least not in all respects), how shall we describe this intermediate state? Also, should we regard any departure from constancy as a failure of the visual system, or might it be a reasonable or adaptive response? In what circumstances is seeing highly conditioned by cognitive factors such as background assumptions, and in what circumstances not? Our volume focuses on size constancy and color constancy. It considers methodologies for studying conscious visual perception, efforts to describe visual experience in relation to constancy, what it means that constancy is not always perfect, and the conceptual resources needed for explaining visual experience. (shrink)

This chapter reconsiders the notion of perceptual constancy from the ground up. It distinguishes the phenomenology of perceptual constancy and stability from a functional characterization of perception as aiming at full constancy. Drawing on this distinction, we can attend to the phenomenology of constancy itself, and ask to what extent human perceivers attain constancy, as usually defined. Within this phenomenology, I distinguish phenomenal presentations of spatial features and color properties from categorizations, conceptualizations, and judgments (...) that underlie verbal or other responses to those presentations. Although phenomenal presentation and categorization commonly co-occur, they are distinct aspects of experience. After reviewing several standard descriptions of constancy, I present laboratory findings and my own phenomenological descriptions by way of confirming that, although perception "tends toward" constancy, human perceivers do not usually attain full constancy for either spatial or chromatic properties (as many investigators acknowledge). For spatial perception, I find that the phenomenology has been systematically misdescribed, and I offer a more adequate description of the phenomenology of everyday spatial perception. However, my greatest quarrel with previous theory concerns the functional aim of the constancies. I argue not only that perception does not achieve full constancy but that we should not characterize it as aiming for full constancy. Rather, perception seeks a stability of representation suitable for guiding our actions and which can also, as needed, enable us to classify and re-identify objects by phenomenally presented properties such as shape, size, or color. Further, I argue that theorists should not confuse these classifications with the qualitative character of phenomenal experience. My arguments underscore the need to distinguish phenomenal representation (better, "presentation") from conceptual categorization, and to distinguish perceptual presentations from subsequent processes that are involved in responding to them. (shrink)

Every perceptual experience has an objective and a subjective side. We see object size, independent of distance, but we also see that distant objects project smaller images. Early modern conceptions focused on local stimulation and thus on the subjective aspect. Helmholtz and Hering emphasized the objective aspect. Helmholtz split visual experience into two stages, with sensation representing the subjective side and perception, through cognitive processes, the objective side. Gestalt theory denied this dualism, rejecting both sensory and cognitive stages. Despite (...) contrary evidence, the sensation/perception dualism persists, in brightness models and past experience theories. That we can detect visual angle and luminance does not mean that these are raw sensations out of which perception of size and lightness is built. Size and color constancy are truly visual, not cognitive. Instructions to subjects in vision experiments must avoid the proximal mode on the one hand and cognitive judgments on the other. (shrink)

The phenomenon of size constancy is defined as the apparent perceptual invariance of the linear dimensions of a seen object as this approaches the eye or recedes from it. It has been interpreted as resulting from the application by the brain of a size correction, made possible by the subject's apprehension of distance cues present in the image. We present several observations which, by dissociating accommodation from distance of the seen object and by suppressing the optic effects (...) of accommodation on the visual image itself, show that this interpretation is incorrect, and that in fact the size correction of the visual image is a function of the central effort of accommodation, not of the distance of the seen object. (shrink)

I agree with most of Mr. Kemp's paper, “Generalization in the Philosophy of Art” but on his position at one point I should like briefly to comment.

I agree with most of Mr. Kemp's paper, “Generalization in the Philosophy of Art” but on his position at one point I should like briefly to comment.

In his interesting discussion of Mr. C. B. Martin's Mind article “A Religious Way of Knowing,” Mr. W. D. Glasgow ;“Knowledge of God”), agrees with Martin that emotions and feelings are part of what we call an aesthetic experience, and also that emotions and feelings are part of what we call a religious experience. “In this sense, at any rate,” Glasgow writes, “there is an analogy between aesthetic experience and religious experience. But...” he goes on, “are aesthetic statements more than (...) statements about emotions and feelings? Are statements about religious experience anything more than statements about emotions and feelings? A person could accept the analogy and yet maintain that for him aesthetic judgments have an objective reference. In this case the analogy confirms rather than destroys the existential claim of the theologian.”. (shrink)

A crucial factor in how we perceive social groups involves the signals and cues emitted by them. Groups signal various properties of their constitution through coordinated behaviors across sensory modalities, influencing receivers' judgments of the group and subsequent interactions. We argue that group communication is a necessary component of a comprehensive computational theory of social groups.

Some experiments in perceptual psychology measure perceivers’ phenomenal experiences of objects versus their cognitive assessments of object properties. Analyzing such experiments, this article responds to Pizlo’s claim that much work on shape constancy before 1985 confused problems of shape ambiguity with problems of shape constancy. Pizlo fails to grasp the logic of experimental designs directed toward phenomenal aspects of shape constancy. In the domain of size perception, Granrud’s studies of size constancy in children and (...) adults distinguish phenomenal from cognitive factors. (shrink)

Humans have undergone a long evolutionary history of violent agonistic exchanges, which would have placed selective pressures on greater body size and the psychophysical systems that detect them. The present work showed that greater body size in humans predicted increased knockout power during combative contests (Study 1a-1b: total N = 5,866; Study 2: N = 44 openweight fights). In agonistic exchanges reflective of ancestral size asymmetries, heavier combatants were 200% more likely to win against their lighter counterparts (...) because they were 200% more likely to knock them out (Study 2). Human dominance judgments (total N = 500 MTurkers) accurately tracked the frequency with which men (N = 516) knocked out similar-sized adversaries (Study 3). Humans were able to directly perceive a man’s knockout power because they were attending to cues of a man’s body size. Human dominance judgments—which are important across numerous psychological domains, including attractiveness, leadership, and legal decision-making—accurately predict the likelihood with which a potential mate, ally, or rival can incapacitate their adversaries. (shrink)

Students of perception have long known that perceptual constancy is an important aspect of our perceptual interaction with the world. Here is a simple example of the phenomenon concerning color perception: there is some ordinary sense in which an unpainted ceramic coffee cup made from a uniform material looks a uniform color when it is viewed under uneven illumination, even though the light reflected by the shaded regions to our eyes is quite different from the light reflected by the (...) unshaded regions to our eyes (see figure 1). Or consider this example concerning size perception: there is some ordinary sense in which two telephone poles look the same size when the first is viewed from 100 meters and when the second is viewed from 1 meter, even though the visual angle subtended by the two poles on our retinae is very different (see figure 2). Or consider this example concerning shape perception: there is some ordinary sense in which a penny looks round both when viewed head on and when viewed from an acute angle, even though the area projected by the penny onto our retinae under these two conditions is very different (see figure 3). Or, finally, consider this example concerning auditory volume perception (which I cannot depict graphically): there is some ordinary sense in which a speaker’s voice sounds the same volume when heard from across the room and when heard from a distance of 1 meter, even though the energy striking our ears under these two conditions is very different. (shrink)

Perceived size is a function of viewing distance, retinal images size, and various contextual cues such as linear perspective and the size and location of neighboring objects. Recently, we demonstrated that illusion magnitudes of classic visual size illusions may be greatly enhanced or reduced by adding dynamic elements. Specifically, a dynamic version of the Ebbinghaus illusion (classically considered a “size contrast” illusion) led to a greatly enhanced illusory effect, whereas a dynamic version of the Corridor (...) illusion (a “size constancy” illusion) led to a greatly diminished illusory effect. Although these differences may arise from the different processes underlying these illusions (size contrast vs. size constancy), the dynamic variants we tested in our previous work also differed in the nature of the dynamic elements; specifically, whereas the Dynamic Ebbinghaus included a moving target and inducers that changed size and position, the Dynamic Corridor only included a moving target on a static background. Here, we explore further dynamic versions of the Ebbinghaus illusion and the Corridor and Ponzo illusions by separately manipulating three types of dynamic elements: target motion, context translation, and dynamic changes in context. Across five experiments examining 21 dynamic illusory configurations, adding target motion or a dynamically changing context separately resulted in little-to-no illusory effect. In contrast, the combination of target motion and a dynamically changing context led to a robust size illusion, consistent with an interactive effect. However, illusory effects that exceeded the matched classic, static illusory configuration were only observed for the dynamic versions of the Ebbinghaus illusion and the Revealed Ponzo illusions, in which the contextual elements changed size. We conclude that the combination of target motion and a dynamically changing context are necessary to produce dynamic size illusions, but that enhancement above and beyond static illusions may be largely specific to size contrast effects. Our results have important implications for the integration of motion signals, a ubiquitous environmental stimulus, in the perception of object size. (shrink)

Naive observers viewed a sequence of colored Mondrian patterns, simulated on a color monitor. Each pattern was presented twice in succession, first under one daylight illuminant with a correlated color temperature of either 16,000 or 4,000 K and then under the other, to test for color constancy. The observers compared the central square of the pattern across illuminants, either rating it for sameness of material appearance or sameness of hue and saturation or judging an objective property—that is, whether its (...) change of color originated from a change in material or only from a change in illumination. Average color constancy indices were high for material appearance ratings and binary judgments of origin and low for hue–saturation ratings. Individuals’ performance varied, but judgments of material and of hue and saturation remained demarcated. Observers seem able to separate phenomenal percepts from their ontological projections of mental appearance onto physical phenomena; thus, even when a chromatic change alters perceived hue and saturation, observers can reliably infer the cause, the constancy of the underlying surface spectral reflectance. (shrink)

We perceive the objective world through a subjective perceptual veil. Various perceived properties, particularly “secondary qualities” like colours and tastes, are mind-dependent. Although mind-dependent, our knowledge of many facts about the perceptual veil is immediate and secure. These are well-known facets of sense-datum theory. My aim is to carve out a conception of sense-datum theory that does not require the immediate and secure knowledge of a wealth of facts about experienced sense-data (§1). Such a theory is of value on its (...) own, given well-known challenges to epistemic foundationalism. Beyond this such a theory helps demonstrate how sense-datum theory can accommodate challenging perceptual phenomena like shape and size constancies (§3). These ideas are bridged by the roots of perceptual ambiguity (§2). In brief, tapering acquaintance knowledge creates space for perceptual representation to resolve the ambiguities in presented objects seemingly inherent in scenarios involving perceptual constancies. Thus, I offer a two-factor (acquaintance-representation) sense-datum theory to meet the challenge posed by constancies. Following Smith (2002), from whom this challenge is drawn, my focus is on shape and size constancies. Other constancies, notably colour constancy, are treated elsewhere (Brown 2014). (shrink)

In an article in Mind (Vol. 73, No. 291, July 1964) I tried to show that there is a fundamental difference between primary and secondary qualities. The present analysis of perceived size of an object and its relation to the size of the 'objective' and the 'real' object reveals that my thesis 1 regarding visual primary qualities, viz. size and shape, while true so far as shape is concerned, has to be modified in regard to size. (...) After having criticized the usual view of size constancy, I show by means of a diagram how we may determine the location in physical space of a percept of an object. This diagram reveals at the same time how perceived size decreases gradually with increasing distance of the object from the percipient, but at a much smaller rate than the retinal image of the object. By means of the diagram I show furthermore how the perceived size may in theory vary from person to person. In conclusion a modification of my thesis 1 is suggested. (shrink)

Philosophers have long sought to explain perceptual constancy—the fact that objects appear to remain the same color, size and shape despite changes in the illumination condition, perspective and the relative distance—in terms of a mechanism that actively categorizes variable stimuli under the same pre-formed conceptual categories. Contemporary representationalists, on the other hand, explain perceptual constancy in terms of a modular mechanism that automatically discounts variation in the visual field to represent the stable properties of objects. In this (...) paper I argue that while the former view is unmotivated by empirical evidence, the later fails to account for inter- and intra-personal variability, the influence of expectations on constancy, and the systematic and normal failures of color constancy. A Bayesian approach that builds on the representational tradition in psychology solves both problems. (shrink)

Lehar argues that a simple Neuron Doctrine cannot explain perceptual phenomena such as size constancy but he fails to discuss existing, more complex neurological models. Size models that rely purely on scaling for distance are sparse, but several models are also concerned with other aspects of size perception such as geometrical illusions, relative size, adaptation, perceptual learning, and size discrimination.

From cytological examination, the size and form of the chromosomes in the eukaryotic nucleus are invariant across generations, leading to the expectation that constancy of inheritance likely depends on constancy of the chromosomal DNA molecule conveying the constant phenotype. Indeed, except for rare mutations, major phenotypic traits appear largely without change from generation to generation. Thus, when it was discovered that the inheritance of traits for bacteria, mitochondria and chloroplasts was also constant, it was assumed that chromosomes (...) in those locations were also constant. Such has not turned out to be the case, however; those chromosomes are highly variable in structure. I propose, therefore, that only for the nucleus is there a requirement that a chromosome be “finished” (contain only fully replicated genomes) before it may segregate to daughter cells. This requirement does not apply to the variable chromosomes among chloroplasts, mitochondria and bacteria. BioEssays 29:474–483, 2007. © 2007 Wiley Periodicals, Inc. (shrink)

The standard way to test alternative descriptive theories of moral judgment is by asking subjects to evaluate (amongst others) sacrificial dilemmas, where acting classifies as a utilitarian moral judgment and not acting classifies as a deontological moral judgment. Previous research uncovered many situational factors that alter subject’s moral judgments without affecting which type of action utilitarianism or deontology would recommend. This literature review provides a systematic analysis of the experimental literature on the influence of situational factors on moral (...) class='Hi'>judgments in sacrificial dilemmas. It analyses 53 articles in detail and reports mean effect sizes, as well as operationalizations, for 36 situational factors that significantly influence moral judgment. Moreover, the review discusses how the impact of situational factors relates to a dual process theory of moral judgment. It supports the view that utilitarian judgments are driven by controlled cognitive processes and shows that the drivers of deontological judgments depend on valence. (shrink)

The COVID-19 pandemic created enormously difficult decisions for individuals trying to navigate both the risks of the pandemic and the demands of everyday life. Good decision making in such scenarios can have life and death consequences. For this reason, it is important to understand what drives risk assessments during a pandemic, and to investigate the ways that these assessments might deviate from ideal risk assessments. In a preregistered online study of U.S. residents (N = 841) using two blocks of vignettes (...) about potential COVID exposure scenarios, we investigated the effects of moral judgment, importance, and intentionality on COVID infection risk assessments. Results demonstrate that risk judgments are sensitive to factors unrelated to the objective risks of infection. Specifically, activities that are morally justified are perceived as safer while those that might subject people to blame or culpability, are seen as riskier, even when holding objective risk fixed. Similarly, unintentional COVID exposures are judged as safer than intentional COVID exposures. While the effect sizes are small, these findings may have implications for public health and risk communications, particularly if public health officials are themselves subject to these biases. (shrink)

Numerous studies show that language can influence both perceptual judgments, as well as the mental categorization of objects in memory. Previous research showed that using diminutive names of objects resulted in being less satisfied with owning said objects and lowering their perceived value. In the present studies, to explore this phenomenon, we decided to investigate whether the influence of a diminutive on the reduction in the subjective value of an object is determined by the perceived size of the (...) object, in accordance with the „bigger is better” heuristic. In Study 1 participants estimated a banknote to be smaller when it was presented with a diminutive label “banknocik” than “banknot”. However, this was not related to the perceived subjective value of the banknote. In Study 2 participants declared that they could buy less with a coin labeled as “pieniążek” than “pieniądz”, but the effect was not linked to the perceived size of the coins. In Study 3 a candy bar labeled as “batonik” was evaluated worse than the same product labeled “baton”, however, once again this was not related to the evaluation of its size. Thus, we show that the effect of diminutives on the reduction in the subjective value of an object is independent of the evaluation of the size of the object and we consider other explanations for the occurrence of this phenomenon. (shrink)

Psychophysical scaling models of the form R = f, with R the response and I some intensity of an attribute, all assume that people judge the amounts of an attribute. With simple biases excepted, most also assume that judgments are independent of space, time, and features of the situation other than the one being judged. Many data support these ideas: Magnitude estimations of brightness increase with luminance. Nevertheless, I argue that the general model is wrong. The stabilized retinal image (...) literature shows that nothing is seen if light does not change over time. The classification literature shows that dimensions often combine to produce emergent properties that cannot be described by the elements in the stimulus. These and other effects cannot be adjusted for by simply adding variables to the general model because some factors do not combine linearly. The proposed alternative is that people initially judge the entire stimulus – the object in terms of its environment. This agrees with the constancy literature that shows that objects and their attributes are identified through their relations to other aspects of the scene. That the environment determines judgments is masked in scaling studies where the standard procedure is to hold context constant. In a typical brightness study the essential stimulus might be the intensity of the light or a difference between the light and the background. The two are perfectly confounded. This issue is examined in the case of audition. Judgments of the loudness of a tone depend on how much that tone differs from the previous tone in both pitch and loudness. To judge loudness people first seem to process the stimulus object in terms of differences between it and other aspects in the situation; only then do they assess the feature of interest. Psychophysical judgments will therefore be better interpreted by theories of attention that are based in biology or psychology than those that are based in classical physics. (shrink)