The goal of this paper is to challenge the rather insouciant attitude that many investigators seem to adopt when they go about describing the items and events in their " visual fields". There are at least three distinct categories of interpretation of what these reports might mean, and only under one of those categories do those reports have anything resembling an observational character. The others demand substantive revisions in one's beliefs about what one sees. The ur-concept of a " visual (...) field" is that of the "sum of things seen", but one can interpret the latter in very different ways. The first is the "field of view", or the sum of physical things seen. The second is an array of visual impressions, whose spatial relations are distinct from those of physical phenomena in front of the eyes. The third is an intentional object: the world as it is represented visually. These three categories are described, and various locutions of vision science--such as "optic array", "retinocentric space", " visual geometry", "virtual object" and others--are analyzed and variously located within them. Finally, a recent argument purporting to necessitate the existence of a version two visual field is examined and shown wanting. (shrink)

Drawing on the findings of neuroscience, this text proposes and defends the hypothesis that the various modalities of sensation share a generic form that the author, Austen Clark, calls feature-placing.

In this paper I begin by considering Travis’s main argument against a representational view of experience. I argue that the argument succeeds in showing that representation is not essential to experience. However, I argue that it does not succeed in showing that representation is not an essential component of experience enjoyed by creatures like us. I then provide a new argument for thinking that the perceptual experience of earthly creatures is representational. The view that ensues is compatible with a certain (...) relational view of experience but entails a rejection of representationalism. (shrink)

A theoretical pillars of vision science in the information-processing tradition is that perception involves unconscious inference. The classic support for this claim is that, since retinal inputs underdetermine their distal causes, visual perception must be the conclusion of a process that starts with premises representing both the sensory input and previous knowledge about the visible world. Focus on this “argument from underdetermination” gives the impression that, if it fails, there is little reason to think that visual processing involves unconscious inference. (...) Here an alternative means of support for this pillar is proposed, based on another foundational challenge for the visual system: recognizing invariant properties of objects in the environment even though anything we encounter is never seen exactly the same way twice. Explaining how the visual system solves this invariance problem requires positing visual processes that exhibit many commonalities with inductive inference. Thus, this novel “argument from invariance” reveals one way in which visual processing clearly involves unconscious inference. (shrink)

The Müller-Lyer illusion is the natural consequence of the construction of the vertebrate eye, retina and visual processing system. Due to imperfections in the vertebrate eye and retina and due to the subsequent processing in the system by ever increasing receptive fields, the visual information becomes less and less precise with respect to exact location and size. The consequence of this is that eventually the brain has to calculate a weighted mean value of the information, which is spread out over (...) a population of neurons. In the case of the Müller-Lyer illusion this inevitably leads to extension of one and reduction of the other line. The arguments presented explain several published experimental results concerning the Müller-Lyer illusion and shed new light upon the philosophical neutrality of observation sentences. (shrink)

The competence of humans to create and apply constructs of reality far exceeds that of any other animal species. Their ability to consciously manipulate such models seems unique, but it remains unknown how these abilities were initially acquired and then developed. Most individuals hold strong, culturally-anchored beliefs that their particular reality is true, a viewpoint challenged by the observation that all such constructs are different. They reflect not reality, but each individual’s life experiences. Collectively they facilitated the development of hominins (...) to unprecedented cultural and cognitive complexity. However, it remains entirely unknown how the human brain manages to create a model of the external world from the signals provided by sensory equipment and proprioceptors. This paper examines the roles of exograms in this development, as they are considered to be the only tangible connection between the brain, the faculties of sentience and the external world. Competency in exogram use became a crucial natural selection factor for humans and even overcame the human brain atrophy of the final Pleistocene and the Holocene. Under favourable conditions, some forms of exograms are capable of surviving from the deep time of human evolution. The paper follows their trail back in time to gain some insights into the developments that gave rise to human awareness, self-consciousness and Theory of Mind as we understand them. Specific archaeological finds and notions about sentient capabilities of hominins are presented in a search for exogram use in the course of human evolution. It results in a model that explains with clarity not only the course of the human journey but also the underlying reasons for the human condition as such: why we are the way we are. (shrink)

Nowadays cognitive science often views sensorial presentations and mental presentations as mutually exclusive, and they are also given separate treatment by neurophysiologists and by cognitive scientists, and some phenomena (like anomalous surfaces or various types of imagery) are reduced to either the former or the latter. Since no adequate methods for its investigation have been developed, the level of perceptual experiences analysed by Gestaltists and magnificently illustrated by Metzger in his Laws of Seeing remains unexplored. Starting from Metzger’s analyses the (...) paper deals with the question of the theoretical value of experimental phenomenology to the theory of knowledge and ontology. (shrink)

A number of studies in the apparent motion literature were examined using the cognitive penetrability criterion to determine the extent to which beliefs affect the perception of apparent motion. It was found that the interaction between the perceptual processes mediating apparent motion and higher order processes appears to be limited. In addition, perceptual and inferential beliefs appear to have different effects on perceived motion optimality and direction. Our findings suggest that the system underlying apparent motion perception has more than one (...) stage and is informationally encapsulated from cognitive factors. (shrink)