Dispositional optimism is typically defined in terms of generalized positive expectancies for personal future life outcomes. Yet, multiple lines of inquiry have demonstrated fundamental interconnections among all three temporal perspectives (past, present, and future). Hence, in the present work, we examine the commonality underlying dispositional optimism and individuals’ evaluations of their past, present, and anticipated future lives. Results (n = 459; 80% female; M age = 19.68) suggest that dispositional optimism loads strongly on an underlying (latent) tendency to evaluate one’s life positively across temporal perspectives. This latent tendency was significantly associated with each Big Five personality dimension; independent of this latent tendency dispositional optimism was associated only with neuroticism. Controlling for personality dimensions, the latent tendency was predictive of positive functioning (mental health, coping, physical health, and social resources); in contrast, independent of this latent tendency dispositional optimism had no significant residual associations with any of the various functioning indicators.