Piaget defines intelligence as adaptation, or the ability to maintain a balance between stability and change, or, in his own words, between assimilation and accommodation. When people assimilate the world to their current knowledge, they impose their order upon things. This momentary closure is useful to build "invariants " that lend existence to the world, independent of immediate interaction. In accommodation, people become one with the object of attention. This may lead to momentary loss of control, since fusion loosens boundaries, but allows for change. I choose the domain of perspective-taking to illustrate how this alternation between assimilation and accommodation punctuate individuals ' interactions with the world. I show that the ability to move away from one's own standpoint, and to take on another person's view, requires the construction of cognitive invariants: a recasting of the world's stabilities that transcends any given viewpoint. I conclude that separation is a necessary step toward the construction of a deeper understanding, and that adopting a "god's eyes view " is by no means contrary to situating one's one stance in the world.

Fourteen- and 18-month-old infants observed an adult experiencing each of 2 objects (experienced objects) and then leaving the room; the infant then played with a 3rd object while the adult was gone (unexperienced object). The adult interacted with the 2 experienced objects in 1 of 3 ways: by (a) sharing them with the infant in an episode of joint engagement, (b) actively manipulating and inspecting them on his or her own as the infant watched (individual engagement), or (c) looking at them from a distance as the infant played with them (onlooking). As evidenced in a selection task, infants of both ages knew which objects had been experienced by the adult in the joint engagement condition, only the 18-montholds knew this in the individual engagement condition, and infants at neither age knew this in the onlooking condition. These results suggest that infants are 1st able to determine what adults know (have experienced) on the basis of their direct, triadic engagements with them.

We outline a new computational account of learning in children using the causal Bayes net formalism. We also present evidence that children as young as two years old use something like causal Bayes net learning mechanisms to infer the causal structure of the world around them. This kind of learning may play an important role in the development of intuitive theories. Finally we contrast causal Bayes net and neural net learning mechanisms.

ABSTRACT—In two experiments, we investigated whether 13-month-old infants expect agents to behave in a way that is consistent with information to which they have been exposed. Infants watched animations in which an animal was either provided information or prevented from gathering information about the actual location of an object. The animal then searched successfully or failed to retrieve the object. Infants ’ looking times suggest that they expected searches to be effective when—and only when—the agent had had access to the relevant information. This result supports the view that infants possess an incipient metarepresentational ability that permits them to attribute beliefs to agents. We discuss the viability of more conservative explanations and the relation between this early ability and later forms of theory of mind that appear only after children have become experienced verbal communicators. Current accounts of the conceptual competence underlying infants’ understanding of agents have emphasized infants ’ ability to represent the goal of an action (Gergely & Csibra, 2003), as well as agents ’ internal source of energy (Leslie, 1994; Luo & Baillargeon, 2005). By their first birthday, infants distinguish agents from inanimate objects (Mandler, 2004), interpret behaviors as goal directed (Baldwin & Baird, 2001; Gergely, Nádasdy,

useful comments on earlier drafts of this article and the staff at the DPSS, University of Padua, the parents and infants for their kind help. Attribution of beliefs by 13-month-olds 2 In two experiments, we investigated whether 13-month-old infants expect agents to behave in a way consistent with information to which they have been exposed. Infants watched animations in which an animal was either provided information or prevented from gathering information about the actual location of an object. The animal then searched successfully or failed to retrieve it. Infants’ looking times suggest that they expected searches to be effective when—and only when—the agent had had access to the relevant information. This result supports the view that infants ’ possess an incipient metarepresentational ability that permits them to attribute beliefs to agents. We discuss the viability of more conservative explanations and the relationship between this early ability and later forms of ‘theory of mind ’ that appear only after children have become experienced verbal communicators. Attribution of beliefs by 13-month-olds 3

Over the preschool years, children develop an understanding of the relationship between their senses and the kinds of knowledge those senses acquire. This development may be supported by sensory experiences or may be linked to theoryof-mind development. 64 preschoolers were asked to identify which of 2 confederates knew the identity of a toy animal when each had differential perceptual access to the animal. In the “seeing ” condition, one confederate looked at the animal and one did not, and in the “hearing ” condition, one confederate listened to the animal’s sound and one did not. 4-year-olds outperformed 3-year-olds in both conditions, and all children performed equally well on both vision and hearing trials suggesting that children come to understand the seeingknowing and hearing-knowing connections simultaneously. Findings provide initial evidence that theory-of-mind rather than experiential learning is most closely related to developing an understanding of the link between sensory perception and knowledge.

People are amateur social psychologists: they explain other people’s behavior, infer what other people are thinking and feeling, and predict how other people will act. I will refer to this sort of psychologizing as social reasoning in order to highlight the fact that it involves reasoning about people. Social reasoning often requires significant leaps of inductive inference: people infer others ’ mental states, such as their preferences, goals, and beliefs, from relatively sparse information, such as others ’ choices and actions. The capacity to reason about mental states and about how mental states relate to behavior is often referred