The current study tests the affect control theory of self, a mathematical theory that demonstrates a core social psychological principle: individuals strive for a stable and coherent self through identity selection and behavior. In the affect control theory of self, the self is conceptualized as self‐sentiments, which are measured on three dimensions: evaluation (good/bad), potency (powerful/powerless), and activity (fast/slow). In a longitudinal sample of college men and women, I find the self‐sentiment predicts how individuals describe themselves on a range of terms, including primary emotions and both stigmatized and esteemed traits related to mental illness and self‐esteem. It also predicts various productive and deviant behaviors five months later. Thus, the current study demonstrates the theoretical precision of the theory, its ability for understanding human behavior, and its potential for identifying at‐risk individuals.