OBJECTPERMANENCE
Object permanence
Object permanence is the understanding that objects continue to exist even when they cannot be observed . This is a fundamental concept studied in the field of developmental psychology, the subfield of psychology that addresses the development of infants' and children's social and mental capacities. There is not yet scientific consensus on when the understanding of object permanence emerges in human development. Some researchers contend that it is acquired within the first two years of life, while others believe that it is an innate or built-in understanding present at birth.The above text is a snippet from Wikipedia: Object permanence
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