David Premack

David Premack (October 26, 1925 – June 11, 2015) was Emeritus Professor of Psychology at the University of Pennsylvania, United States. He was educated at the University of Minnesota when logical positivism was in full bloom. The departments of Psychology and Philosophy were closely allied. Herbert Feigl, Wilfred Sellars, and Paul Meehl led the philosophy seminars, while Group Dynamics was led by Leon Festinger and Stanley Schachter.

Premack started in primate research in 1954 at the Yerkes Primate Biology Laboratory at Orange Park outside Jacksonville, Florida. His first two chimpanzee subjects, Sarah and Gussie, started at the University of Missouri and traveled with him to the University of California, Santa Barbara, and then to the University of Pennsylvania, where he had nine chimpanzee subjects.

Premack's first publication (1959) was a new theory of reinforcement (which became known as Premack's principle). It argued that the more probable response in any pair of responses could reinforce the less probable response—demonstrating that reinforcement is a relative, not an absolute property.

This theory predicts six conditions, all of which have been supported by evidence:

Premack introduced the concept of Theory of Mind, with Guy Woodruff, in an article published in 1978. This has proven to be a fruitful concept in psychology and neuroscience. For example, hundreds of articles have been published on theory of mind in fields ranging from comparative psychology studies of cognitive capacities of animals to human developmental psychology studies of infant cognition to social neuroscience studies of the brain substrates that mediate simulations of mental processes in other individuals.

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