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Abstract--- Constructivist learning is a hierarchical part-towhole learning system used by humans and desirable for use by robots. Current implementations are too resourceintensive to be used for anything but simple environments. In this paper, we reimplement one such system, the Schema Mechanism, using a hierarchy of self-organizing maps. The result is an efficient system for learning perceptual and action schemas that can be used in real-world applications

The acquisition of infant causal perception has been the center of considerable debate, and some have attributed this phenomenon to an innate causal module. Recent studies, however, suggest that causal knowledge may develop in infants through experience with the environment. We present a computational model of causal knowledge acquisition built using the Constructivist Learning Architecture, a hierarchical self-organizing system. This system does a remarkably good job of developing causal perception from a component view to a holistic view in a way that mirrors data from habituation studies with human infants. Causal Perception in Infants Causal perception has been the focus of philosophical inquiry for centuries, but it received its first notable psychological investigation by Michotte (1963). He presented adults with a scene in which one billiard ball struck another stationary ball, resulting in the launching of the stationary ball, and the halting of the moving ball. T...

Considerable evidence has now accumulated that pre-verbal infants expect that an inanimate object can be caused to move only by physical contact. However, very few studies have investigated infants ’ expectations about the source of causal power. In 3 experiments, we found that (i) 10 and 12 month old infants expect a human hand, and not an inanimate object, as the primary cause of an inanimate object’s motion, (ii) the infants ’ expectations can lead them to infer a hidden causal agent without any direct perceptual evidence, and (iii) infants did not infer a hidden causal agent if the moving object was previously shown to be capable of self-generated motion. 2 Causal attributions are central to human cognition, underlying representations of concepts and intuitive theories (Carey, 1985; Gopnik et al., 2004; Keil, 1989; Murphy, 2002), supporting prediction of future events, and allowing effective intervention in the service of our goals. The capacity for causal attribution emerges early in infancy, and is embedded in at least two distinct domains of reasoning, reasoning about inanimate objects for which the cause of motion must

Piagetian constructivism, an attractive model of grounded knowledge acquisition, has been shy on details, making modeling difficult. New research in developmental cogition has shed some light on these details. More accurate and powerful constructivist models can now be built, and one such model -- the Constructivist Learning Architecture -- is proposed.

Words, kinds and causal powers: A theory theory perspective on early naming and categorization. For some twenty-five years, the prevailing theories of categorization in philosophy have invoked the idea of “kinds ” (Putnam, 1975; Kripke, 1972). When we look at how adults use words to refer to categories of things we find that they only rarely categorize objects on the basis of their common properties. Instead, adults seem to categorize objects together when they believe that they belong to the same “kind”; that is, that they share some common, abstract “essence.” Psychological investigations of adults have largely confirmed these philosophical intuitions, adults do seem to group objects together based on “kinds ” rather than properties (Murphy &

Infants aged 4 and 6 months were presented with events in which a person acted so as to set another person, or an inanimate object, in motion. In one condition, the actor spoke to the person (natural) or inanimate object (unnatural); in the other condition, the actor grasped and manipulated the person (unnatural) or object (natural). Six-month-old infants looked reliably longer at the natural actions than at the unnatural actions. A follow-up experiment revealed that their preference depended on the naturalness of the human actions themselves, not on the features or motions of the person or object that was acted upon. Looking preferences at 4 months were equivocal, consistent with the thesis that sensitivity to the natural actions develops over the first 6 months of age. We discuss these findings in relation to the development of social understanding, social gaze, and visual exploration. A growing body of research provides evidence that infants become sensitive to distinctions between inanimate objects and persons within the first 6 months of life (for reviews see Johnson, 2000; Poulin-Dubois, 1999, and Spelke, Phillips & Woodward, 1995). In studies using preferential looking methods, for example, 6-month-old infants apparently represent the successive motions of two inanimate objects as causally related only if the objects come into contact (Ball, 1973; Leslie, 1988; Oakes & Cohen, 1995), whereas they represent similar motions of two animate agents as causally related without contact (Csibra, Gergely, Biro, Koos, & Brockbank, 1999; Gergely, Nadasdy, Csibra & Biro, 1995; Woodward, Phillips & Spelke, 1993). Five-month-old infants also react to changes in the goal of a human reach, whereas they show no such reaction to the motions of inanimate objects (Woodward, 1998, 199...

This paper addresses questions about how the levels of causality (generic and single-case causality) are related. One question is epistemological: can relationships at one level be evidence for relationships at the other level? We present three kinds of answer to this question, categorised according to whether inference is top-down, bottom-up, or the levels are independent. A second question is metaphysical: can relationships at one level be reduced to relationships at the other level? We present three kinds of answer to this second question, categorised according to whether single-case relations are reduced to generic, generic relations are reduced to single-case, or the levels are independent. We then explore causal inference in autopsy. This is an interesting case study, we argue, because it refutes all three epistemologies and all three metaphysics. We close by sketching an account of causality that

Preverbal infants can represent the causal structure of events, including distinguishing the agentive and receptive roles and categorizing entities according to stable causal dispositions. This study investigated how infants combine these 2 kinds of causal inference. In Experiments 1 and 2, 9.5-month-olds used the position of a human hand or a novel puppet (causal agents), but not a toy train (an inert object), to predict the subsequent motion of a beanbag. Conversely, in Experiment 3, 10- and 7-month-olds used the motion of the beanbag to infer the position of a hand but not of a toy block. These data suggest that preverbal infants expect a causal agent as the source of motion of an inert object.

Dynamics and the perception of causal events To imagine possible events, we use our knowledge of causal relationships. To look deep into the past and infer events that were not witnessed, we use causal relationships as well. We also use causal knowledge to infer what can not be directly seen in the present, for instance, the existence of planets around distant stars, or the presence of subatomic particles. Knowledge of causal relationships allows us to go beyond the immediate here and now. In this chapter I introduce a new theoretical framework for how this very basic concept might be mentally represented. In effect, I propose an epistemological theory of causation, that is, a theory that specifies the nature of people’s knowledge of causation, the notion of causation used in everyday language and reasoning. In philosophy, epistemological theories are often contrasted with metaphysical theories, theories about the nature of reality. Since people’s concepts of causation are assumed to be in error, most metaphysical theories of causation seek to reform rather than describe the concept of CAUSE in people’s heads, (see Mackie, 1974; Dowe, 2000). Theories of causation in psychology have followed suit by linking people’s representations of causation to the outward