The Thomas Theorem

If men define situations as real, they are real in their consequences.

W.I. Thomas and D.S. Thomas, The Child in America: Behavior Problems and Programs (New York: Knopf, 1928). This idea was developed by sociologist Robert K. Merton in regards to “the self-​fulfilling prophecy,” see  “The Thomas Theorem and the Matthew Effect”. Social Forces. 74 (2): 379 – 422.