What psychological theory is associated with the development of a full life, including a meaningful existence?

The theory associated with the development of a full life and a meaningful existence is Positive Psychology. This field of psychology focuses on the study of positive human functioning and flourishing. It emphasizes strengths, virtues, and factors that contribute to a fulfilling life, rather than solely concentrating on pathology or what is wrong with individuals. Positive Psychology encourages individuals to explore aspects such as happiness, well-being, resilience, and personal growth.

While Humanism also addresses meaningful existence and emphasizes personal development and self-actualization, it is broader and does not focus exclusively on the empirical study of positive aspects of life, which differentiates it from Positive Psychology. Similarly, Behaviorism primarily looks at observable behaviors and environmental influences without delving into internal meaning. Cognitive Behavioral Theory focuses on the interplay of thoughts, feelings, and behaviors but does not specifically address the overall sense of meaning and fulfillment that Positive Psychology seeks to cultivate. Thus, Positive Psychology is distinct for its dedicated approach to studying what makes life worth living and how individuals can achieve greater satisfaction and purpose.