For many people, a good life is a stable life, a comfortable life that follows a well-trodden path. This is the case for Shigehiro Oishi's father, who has lived in a small mountain town in Japan for his entire life, putting his family's needs above his own, like his father and grandfather before him. But is a happy life, or even a meaningful life, the only path to a good life?

In Life in Three Dimensions, Shige Oishi enters into a debate that has animated psychology since 1984, when Ed Diener (Oishi's mentor) published a paper that launched happiness studies. A rival followed in 1989 with a model of a good life that focused on purpose and meaning instead. In recent years, Shige Oishi's award-winning work has proposed a third dimension to a good life: psychological richness, a concept that prioritizes curiosity, exploration, and a variety of experiences that help us grow as people.

Life in Three Dimensions explores the shortcomings of happiness and meaning as guides to a good life, pointing to complacency and regret as a "happiness trap" and narrowness and misplaced loyalty as a “meaning trap.” Psychological richness, Oishi proposes, balances the other two, offering insight and growth spurred by embracing uncertainty and challenges.

In a lively style, drawing on a generation of psychological studies and on examples from famous people, books and film, Oishi introduces a new path to a fuller, more satisfying life with fewer regrets.