Assimilation is an aspect of adaptation proposed by French psychologist Jean Piaget.

In the seminal cognitive developmental theory of Jean Piaget (1896–1980), assimilation is one of two complementary activities involved in adaptation. Through studying his own children, Piaget observed the manner in which knowledge actually develops in the mind. Adaptation is the process by which people learn from and adjust to their environment. Assimilation consists of taking in new information and incorporating it into existing ways of thinking about the world. Accommodation, however, necessitates actual change in one's existing ideas to adapt to new information. When infants first learn to drink milk from a cup, for example, they try to assimilate the new experience (the cup) into their existing way of ingesting milk (sucking). When they find that this does not work, they then change their way of drinking milk by accommodating their actions to the cup. The dual processes of accommodation and assimilation lead to the formation and alteration of schemas; these generalizations about the world are formed from past experience and are used to guide individuals through new experiences. According to Piaget, cognitive development involves the constant search for a balance between assimilation and accommodation, which he referred to as equilibration.

In the context of personality, the term assimilation has been used by Gordon Allport (1897–1967) to describe the tendency to fit information into one's own attitudes or expectations. In the study of attitudes and attitude change, it means adopting the attitudes of people with whom one identifies strongly.

See also Acculturation ; Adaptation ; Affiliation ; Piaget, Jean; Piaget's theory of cognitive development .



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