Online research in philosophy

Millikan's discussion of substance concepts in terms of their information-gathering role ignores the analyses of information-based perception and action developed within the tradition of ecological psychology. Her introduction and use without definition of key Gibsonian terms such as “affordance” and “direct perception” leaves those of us investigating such concepts uncertain of the extent to which she appreciates their theoretical importance. Due recognition of the realist account of categorical perception developed by J. J. Gibson would provide mutual benefit to modern externalist philosophy as well as to experimental psychology and to those investigating the ecological approach to perception–action.

The parallel drawn by Norman between the dorsal and ventral systems and direct and indirect approaches is based on two misrepresentations of the direct approach – that it is concerned only with the unconscious control of action, and that it cannot explain learning. We propose a way of understanding the visual system differences from within the direct approach.

Norman's aim to reconcile two longstanding and seemingly opposed philosophies of perception, the constructivist and the ecological, by casting them as approaches to complementary subsystems within the visual brain is laudable. Unfortunately, Norman overreaches in attempting to equate direct perception with dorsal/unconscious visual processing and indirect perception with ventral/conscious visual processing. Even a cursory review suggests that the functional and neural segregation of direct and indirect perception is not as clear as the target article would suggest.

The two contrasting theoretical approaches to visual perception, the constructivist and the ecological, are briefly presented and illustrated through their analyses of space and size perception. Earlier calls for their reconciliation and unification are reviewed. Neurophysiological, neuropsychological, and psychophysical evidence for the existence of two quite distinct visual systems, the ventral and the dorsal, is presented. These two perceptual systems differ in their functions; the ventral system's central function is that of identification, while the dorsal system is mainly engaged in the visual control of motor behavior. The strong parallels between the ecological approach and the functioning of the dorsal system, and between the constructivist approach and the functioning of the ventral system are noted. It is also shown that the experimental paradigms used by the proponents of these two approaches match the functions of the respective visual systems. A dual-process approach to visual perception emerges from this analysis, with the ecological-dorsal process transpiring mainly without conscious awareness, while the constructivist-ventral process is normally conscious. Some implications of this dual-process approach to visual-perceptual phenomena are presented, with emphasis on space perception. Key Words: constructivist; dual-process approach; ecological; size perception; space perception; two visual systems; visual perception theories.

This paper is part of a series in which we had worked in the last 6 months, and, specifically, intend to investigate the notion of timbre through the ecological perspective proposed by James Gibson in his Theory of Direct Perception. First of all, we discussed the traditional approach to timbre, mainly as developed in acoustics and psychoacoustics. Later, we proposed a new conception of timbre that was born in concepts of ecological approach. The ecological approach to perception proposed by Gibson (1966, 1979) presupposes a level of analysis of perceptual stimulated that includes, but is quite broader than the usual physical aspect. Gibson suggests as focus the relationship between the perceiver and his environment. At the core of this approach, is the notion of affordances, invariant combinations of properties at the ecological level, taken with reference to the anatomy and action systems of species or individual, and also with reference to its biological and social needs. Objects and events are understood as relates to a perceiving organism by the meaning of structured information, thus affording possibilities of action by the organism. Event perception aims at identifying properties of events to specify changes of the environment that are relevant to the organism. The perception of form is understood as a special instance of event perception, which is the identity of an object depends on the nature of the events in which is involved and what remains invariant over time. From this perspective, perception is not in any sense created by the brain, but is a part of the world where information can be found. Consequently, an ecological approach represents a form of direct realism that opposes the indirect realist based on predominant approaches to perception borrowed from psychoacoustics and computational approach.

And in the end I came to believe that the whole theory of depth perception was false. I suggested a new theory in a book on what I called the visual world ...

In his ecological approach to perception, james gibson introduced the concept of affordance to refer to the perceived meaning of environmental objects and events. this paper examines the relational and causal character of affordances, as well as the grounds for extending affordances beyond environmental features with transcultural meaning to include those features with culturally-specific meaning. such an extension is seen as warranted once affordances are grounded in an intentional analysis of perception. toward this end, aspects of merleau-ponty's treatment of perception are explored. finally, a resolution of the apparent tension between the relational and perceiver-independent nature of affordances is presented.

This article contributes to understanding the relation within Gibson's perception theory between two questions that Gibson raised in the introductory paragraph of his final book, The Ecological Approach to Visual Perception: (a) how we see how to do things and (b) why things look to us as they do (Koffka's question). Although Gibson considered Koffka's question to be a crucial test for any psychological theory of visual perceiving, Gibson did not explicitly defend his ecological approach with reference to Koffka's question. Gibson's entire final book is not, as some Gibsonians would suggest, Gibson's answer to Koffka's question. However, certain subsidiary parts of the book implicitly and almost explicitly suggest a place in Gibsonian perception theory for the phenomenal looks of things that we visually perceive. The present article considers some Gibsonian answers and reactions to Koffka's question, and argues that the phenomenal looks of things play a crucial role in Gibson's account of the visual control of locomotion.

Fodor & Pylyshyn (1981) criticize J. J. Gibson's ecological account of perception for failing to address what I call the 'correlation problem' in visual perception. That is, they charge that Gibson cannot explain how perceivers learn to correlate detectable properties of the light with perceptible properties of the environment. Furthermore, they identify the correlation problem as a crucial issue for any theory of visual perception, what I call a 'primary problem'—i.e. a problem which plays a definitive role in establishing the concerns of a particular scientific research program. If they are correct, Gibson's failure to resolve this problem would cast considerable doubt upon his ecological approach to perception. In response, I argue that both Fodor & Pylyshyn's problem itself and their proposed inferential solution embody a significant mistake which needs to be eliminated from our thinking about visual perception. As part of my response, I also suggest a Gibsonian alternative to Fodor & Pylyshyn's primary problem formulation.