Patrice D. Tremoulet

Perceptual causality and animacy

Certain simple visual displays consisting of moving 2-D geometric shapes can give rise to percepts with high-level properties such as causality and animacy. This article reviews recent research on such phenomena, which began with the classic work of Michotte and of Heider and Simmel. The importance of such phenomena stems in part from the fact that these interpretations seem to be largely perceptual in nature - to be fairly fast, automatic, irresistible and highly stimulus driven - despite the fact that they involve impressions typically associated with higher-level cognitive processing. This research suggests that just as the visual system works to recover the physical structure of the world by inferring properties such as 3-D shape, so too does it work to recover the causal and social structure of the world by inferring properties such as causality and animacy.

Infant individuation and identification of objects

Abstract Recent studies of the infants object concept have focused on the role of property information in individuation. We draw a distinction between individuation and identification. By individuation, we mean the setting up of an object representation (OR). By identification, we mean using the information stored in an OR to decide which, if any, previously individuated object is presently encountered. We investigate this distinction in experiments with 12-month-old infants. We find that for infants of this age, a shape difference between two objects has a large effect on both individuation and identification. However, a color difference between two objects has a large effect on individuation, but little or no effect on identification. This suggests that, somewhat surprisingly, information used to establish an OR may not always be incorporated into that representation.

Rethinking Rationality: From Bleak Implications to Darwinian Modules

There is a venerable philosophical tradition that views human beings as intrinsically rational, though even the most ardent defender of this view would admit that under certain circumstances people’s decisions and thought processes can be very irrational indeed. When people are extremely tired, or drunk, or in the grip of rage, they sometimes reason and act in ways that no account of rationality would condone. About thirty years ago, Amos Tversky, Daniel Kahneman and a number of other psychologists began reporting findings suggesting much deeper problems with the traditional idea that human beings are intrinsically rational animals. What these studies demonstrated is that even under quite ordinary circumstances where fatigue, drugs and strong emotions are not factors, people reason and make judgments in ways that systematically violate familiar canons of rationality on a wide array of problems. Those first surprising studies sparked the growth of a major research tradition whose impact has been felt in economics, political theory, medicine and other areas far removed from cognitive science. In Section 2, we will sketch a few of the better known experimental findings in this area. We’ve chosen these particular findings because they will play a role at a later stage of the paper. For readers who would like a deeper and more systematic account of the fascinating and disquieting research on reasoning and judgment, there are now several excellent texts and anthologies available. (Nisbett and Ross 1980, Kahneman, Slovic and Tversky 1982, Baron 1988, Piatelli-Palmarini 1994, Dawes 1988, Sutherland 1994).