jan 1, 1954 - Festinger edited an influential book called Research Methods in the Behavioral Sciences,

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"in which he and other social psychologists stressed the need to measure variables and to use laboratory experiments to systematically test research hypotheses about social behavior. He also noted that it might be necessary in these experiments to deceive the participants about the true nature of the research."
https://open.lib.umn.edu/socialpsychology/chapter/1-1-defining-social-psychology-history-and-principles/#:~:text=During%20the%201940s%20and%201950s,as%20a%20rigorous%20scientific%20discipline.

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