Peter Laslett (1915-2001), a British historian, established his rather positive aging theory of the Third Age in the 1980s. In Laslett’s (1987) theory, one’s life comprises four ages, and the culmination is in the Third Age. The phrase Third Age came from French universities, les Universités du Troisième Âge (the Universities of the Third Age), which since the 1970s have offered study opportunities to seniors relatively healthy and active, and entered English-speaking countries (Laslett, 1987).
Laslett (1987) mentioned that the Third Age was generally an era after retirement with health, vigor, and positive attitude to have the Third Age, except for particular cases. He also described that the Third Age emerged in only developed countries with both population aging and excellent economic conditions.
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