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Did neighborhood life‐cycle theory cause urban decline?

Early 20th-century American sociologist William I. Thomas argued that “if men define the situation as real, [it is] real in its consequences” (1928, 31). The concept is simple. Our world is organized as a series of defined situations where many of our actions depend on the nature of the definition. Some contend that the same holds true for neighborhoods. That is, if we define neighborhoods as declining, then, as a self-fulfilling prophecy, they will decline (Jacobs 1961). This issue of Housing Policy Debate presents a Forum on what has become a rather controversial topic: the role that theories of neighborhood change played in causing neighborhood decline.