of DEVELOPMENTAL PSYCHOLOGY

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Kegan. 1982; King & Kitehener, 1994; Kohlberg, 1969; 1984; Loevinger, 1976; Sinnott, 1998). These models either have substantially expanded Piaget’s modelalong the vertical dimensionby adding higher cognitive stages such as post-formaloperations and advanced reflective thinking, or have extended Piagets model along the horizontal dimension by

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