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)

HISTORIANS of psychology are almost unanimously agreed on one point: that psychology is a relatively new science. There may be some disagreement as to when it started--with Weber, or Fechner, or Wundt, or James--but there is almost no dissent from the proposition that psychology as a scientific discipline is less than one and one-half centuries old. Many earlier writers are often discussed in histories of psychology, but invariably they are called speculators, or philosophers, as opposed to scientists. We believe that (...) this is an incorrect appraisal of the career of psychological research. To demonstrate our point, we propose to show how one key psychological idea from Descartes' work has had an extensive and robust scientific history. If it is true that this Cartesian idea has had great influence in science, then many claims concerning the history of psychology will need to be reconsidered. Not everything which happened in psychology prior to the nineteenth century was speculative, nor is everything which happened later scientific. Even more importantly, if Descartes' idea has been of such central concern to several hundred years of research, it must be treated as an important claim about the way the world is, as a law of nature. (shrink)

Hintikka has criticized psychologists for "hasty epistemologizing," which he takes to be an unwarranted transfer of ideas from psychology (a discipline dealing with questions of fact) into epistemology (a discipline dealing with questions of method and theory). Hamlyn argues, following Hintikka, that Gibson's theory of perception is an example of such an inappropriate transfer, especially insofar as Hamlyn feels Gibson does not answer several important questions. However, Gibson's theory does answer the relevant questions, albeit in a new and radical way, (...) which suggests that the alleged distinction between psychology and epistemology is suspect. In fact, contrary to Hintikka and Hamlyn's claims, Gibson's theory of perception appears to be a valuable source of epistemological as well as psychological ideas. (shrink)

The philosophical or metaphysical architecture of Darwin's theory of evolution by natural selection is analyzed and diflussed. It is argued that natural selection was for Darwin a paradigmatic case of a natural law of change — an exemplar of what Ghiselin (1969) has called selective retention laws. These selective retention laws lie at the basis of Darwin's revolutionary world view. In this essay special attention is paid to the consequences for Darwin's concept of species of his selective retention laws. Although (...) Darwin himself explicity supported a variety of nominalism, implicit in the theory of natural selection is a solution to the dispute between nominalism and realism. It is argued that, although implicit, this view plays a very important role in Darwin's theory of natural selection as the means for the origin of species. It is in the context of these selective retention laws and their philosophical implications that Darwin's method is appraised in the light of recent criticisms, and the conclusion drawn that he successfully treated some philosophical problems by approaching them through natural history. Following this an outline of natural selection theory is presented in which all these philosophical issues are highlighted. (shrink)