<p>Positivity, defined as the tendency to view life and experiences with a positive outlook, has recently received a great deal of interest for its significance in understanding human strengths and well-being, yet the temporal interplay among its three facets (self-esteem, life satisfaction, optimism) in relation to the construct of positivity itself is still unclear. A three-wave study of 1,375 Spanish university students investigated this interplay before, during, and after the first COVID-19 lockdown. A Random Intercept Cross-Lagged Panel Model separated trait-like from state-like variance in each facet and extracted latent shared components, to explore the extent to which positivity subsumes or coexists with these dimensions of human strengths and their relationships across time. The trait-like positivity factor loaded strongly on the between-person components of self-esteem, life satisfaction, and optimism, suggesting a pervasive influence on these facets at the between-person level. A state-like positivity factor accounted for their concurrent dynamic fluctuations, but did not fully account for the within-person variance of each facet, showing its distinctiveness from these constructs and the uniqueness of each. Moreover, both trait-like and state-like positivity and within-person residuals of self-esteem, life satisfaction, and optimism were significantly associated with subjective mental health perception. These findings contribute to the understanding of positivity as a construct encompassing a stable trait-like disposition and state-like specific components arising from self-esteem, life satisfaction and optimism without subsuming them, highlighting its role as an expression of the self-system with an important function in well-being and adaptive functioning.</p>