For 10 points, name this Swiss psychologist, who outlined a four-stage model of development.
In one of this man's experiments, subjects are asked which of two differently-spaced rows of the same number of pennies contains more coins. This thinker argued that his subjects used "schemata" to interpret the world, and, when faced with new information, had the dual options of "assimilation" and "accommodation." This developer of "genetic epistemology" described the beginning of egocentrism and the development of object permanence in outlining a theory that includes formal operational and sensorimotor stages. For 10 points, name this Swiss psychologist, who outlined a four-stage model of development.
In one of this man's experiments, subjects are asked which of two differently-spaced rows of the same number of pennies contains more coins.
Jean Piaget