Online research in philosophy

David Marr's theory of vision has been widely cited by philosophers and psychologists. I have three projects in this paper. First, I try to offer a perspicuous characterization of Marr's theory. Next, I consider the implications of Marr's work for some currently popular philosophies of psychology, specifically, the "hegemony of neurophysiology view", the theories of Jerry Fodor, Daniel Dennett, and Stephen Stich, and the view that perception is permeated by belief. In the last section, I consider what the phenomenon of vision must be like for Marr's project to succeed.

The cosmological constant is back. Several lines of evidence point to the conclusion that either there is a positive cosmological constant or else the universe is filled with a strange form of matter (“quintessence”) that mimics some of the effects of a positive lambda. This paper investigates the implications of the former possibility. Two senses in which the cosmological constant can be a constant are distinguished: the capital Λ sense in which lambda is a universal constant on a par with the charge of the electron, and the lower case λ sense in which lambda is a humble constant of integration. The latter interpretation has been touted as the means to a solution to various problems in physics. These claims are critically examined with an eye to discerning the implications for philosophy of science and foundations of physics.

Part 1 describes Stanisaw Jakowski's concept of defining some often used con ditionals, namely, factorial, ewfficient and definitive implications.Part 2 contains the results strictly connected with the theory of the above implications.

According to Marr's theory of vision, computational processes of early vision rely for their success on certain "natural constraints" in the physical environment. I examine the implications of this feature of Marr's theory for the question whether psychological states supervene on neural states. It is reasonable to hold that Marr's theory is nonindividualistic in that, given the role of natural constraints, distinct computational theories of the same neural processes may be justified in different environments. But to avoid trivializing computational explanations, theories must respect methodological solipsism in the sense that within a theory there cannot be differences in content without a corresponding difference in neural states.

The sense of being stared at is the basis of evil eye beliefs, which are regarded as superstitions because the emission of any form of energy from the human eye has been rejected by Western science. However, brainwaves in the 1–40 Hertz, 1–10 microvolt range emitted through the eye can be detected using a high-impedance electrode housed inside electromagnetically insulated goggles. This signal, which the author calls “human ocular extramission,” is physiologically active and has distinct electrophysiological properties from simultaneous brainwave recordings over the forehead. Western science's rejection of evil eye beliefs may be based on an erroneous rejection of a widespread component of human consciousness, the sense of being stared at, which may in turn be based on a real electrophysiological signal. The author proposes a series of future studies designed to determine whether human ocular extramission is the basis of evil eye beliefs.

Most people have had the experience of turning round feeling that someone is looking at them from behind, and finding that this is the case. Most people have also had the converse experience. They can sometimes make people turn around by staring at them. In surveys in Europe and North America, between 70% and 97% of the people questioned said they had had personal experiences of these kinds (Braud et al., 1990; Sheldrake, 1994; Cottrell et al., 1996).

Does your dog know when it is time for walkies, even if you are in a different room when you decide to take it out? Can you sometimes tell that you are being stared at, even when your kibitzer is some distance away and completely hidden? If so, Rupert Sheldrake (www.sheldrake.org) would like to hear from you. He has compiled a database of over 5,000 such cases, and would be glad to learn of any more.