Depth adjacency in simultaneous contrast

The Gelb phenomenon, as an example of whiteness contrast, was investigated with three amounts of separation in depth between the test and induction disc. The cue of binocular disparity was used to vary the perceived depth between the discs. It was found that the magnitude of the contrast effect decreased with an increase in the perceived depth between the two discs. This change was regarded as an instance of the adjacency principle. The problem of whether the binocular disparity cue per se or perceived depth was the significant variable was discussed. The consequences of the results were considered with respect to the relation between whiteness constancy and whiteness contrast and the problem of neural localization of the contrast effect.     

Depth adjacency and induced motion.

Induced motion was investigated as a function of the stereoscopic separation of the test and inducing object and the instructions to attend to or to ignore the inducing object. It was found that stereoscopically displacing the test object from the inducing object with both kinds of instructions resulted in a decrease in the magnitude of induction particularly with crossed disparity. These results are consistent with the adjacency principle and with the ability of attention as well as adjacency to modify the magnitude of the induced motion.     

PSYCHOPHYSICAL INVARIANTS OF ACHROMATIC COLOUR VISION: IV. Depth adjacency and simultaneous contrast

L ie , I. Psychophysical invariants of achromatic colour vision. IV. Depth adjacency and simultaneous contrast. Scand. J. Psychol ., 1969, 10 , 282–286.— Achromatic colour contrast as a function of adjacent subareas was investigated by a stereoscopic depth technique. The degree of colour contrast was found to be independent of stereoscopic depth.     

Depth adjacency and the rod-and-frame illusion

The effects of psychological set on perception of first and second pain were determined for 20 subjects. Percutaneous electrical shock intensities (6–8 mA, 3 msec) sufficient to evoke double pain responses were used in all subjects. Psychological sets included PAST (“Place yourself in a previous experience that was free of any significant emotional tone”), PRESENT (“Feel your foot that will be shocked”), and FUTURE (“Think to yourself that you are about to be shocked”). Perception of second pain was never perceived in PAST and FUTURE sets but was always perceived in the PRESENT set. Furthermore, at minimal rates of stimulation ( > 1/3 sec), summation of second pain occurred in the PRESENT set but not in the FUTURE set. All subjects startled in the FUTURE set and did not startle in PAST or PRESENT sets. Each subject reported that the aversiveness of the shock related to painful sensations in PAST and PRESENT sets and to ones own body responses in the FUTURE set.     

A reply to Mr. Dowling

This paper examines the interpretation of Hobbes as a political formalist which is developed by F. S. McNeilly in The Anatomy of Leviathan. McNeilly argues that Hobbes's demonstration of the necessity of political society is independent of Hobbes's particular view of man as an egotist bent at all costs on his own preservation. The first part of the argument of the paper uses techniques of decision theory and game theory to show that this argument which McNeilly ascribes to Hobbes is not valid. However, the argument which Hobbes is traditionally supposed to put forward is shown to be valid. The second part of the paper examines McNeilly's interpretation of the text of Leviathan and shows that he has insufficient grounds for supposing that Hobbes attempted to construct a purely formal science of politics.     

A utilitarian reply to Dr. McCloskey

A theory of punishment should tell us not only when punishment is permissible but also when it is a duty. It is not clear whether McCloskey's retributivism is supposed to do this. His arguments against utilitarianism consist largely in examples of punishments unacceptable to the common moral consciousness but supposedly approved of by the consistent utilitarian. We remain unpersuaded to abandon our utilitarianism. The examples are often fanciful in character, a point which (pace McCloskey) does rob them of much of their force. If there was no tension between utilitarian precepts and those which come naturally to plain men, utilitarianism could have no claim to provide a critique of moralities. The utilitarian's attitude to such tensions is somewhat complicated, but what is certain is that there is more room in his system for the sentiments to which McCloskey appeals against him than McCloskey realizes. We agree with McCloskey, however, on the absurdity of substituting rule‐utilitarianism for act‐utilitarianism as an answer to his attacks. The distinction itself may represent a conceptual confusion. In our view, indeed, unmodified act‐utilitarianism provides the best moral basis for thought about punishment.     

On inconsistent entities. A reply to Colyvan

In a recent article M. Colyvan has argued that Quinean forms of scientific realism are faced with an unexpected upshot. Realism concerning a given class of entities, along with this route to realism, can be vindicated by running an indispensability argument to the effect that the entities postulated by our best scientific theories exist. Colyvan observes that among our best scientific theories some are inconsistent, and so concludes that, by resorting to the very same argument, we may incur a commitment to inconsistent entities. Colyvan’s argument could be interpreted, and in part is presented, as a reductio of Quinean scientific realism; yet, Colyvan in the end manifests some willingness to bite the bullet, and provides some reasons why we shouldn’t feel too uncomfortable with those entities. In this paper we wish to indicate a way out to the scientific realist, by arguing that no indispensability argument of the kind suggested by Colyvan is actually available. To begin with, in order to run such an indispensability argument we should be justified in believing that an inconsistent theory is true; yet, in so far as the logic we accept is a consistent one it is arguable that our epistemic predicament could not be possibly one in which we are justified in so believing. Moreover, also if our logic admitted true contradictions, as Dialetheism does, it is arguable that Colyvan’s indispensability argument could not rest on a true premise. As we will try to show, dialetheists do not admit true contradictions for cheap: they do so just as a way out of paradox, namely whenever we are second-level ignorant as to the metaphysical possibility of evidence breaking the parity among two or more inconsistent claims; Colyvan’s examples, however, are not of this nature. So, even under the generous assumption that Dialetheism is true, we will conclude that Colyvan’s argument doesn’t achieve its surprising conclusion.