Self-related core beliefs incrementally predict levels and change in life satisfaction over and above the Big Five

Life satisfaction, although relatively stable, also shows considerable variation over time, and individuals typically seek to enhance their overall levels. In this study, we investigate whether self-related core beliefs can predict levels and change in life satisfaction beyond the Big Five traits, providing evidence regarding its nomological net and regarding determinants of change. We present results from a longitudinal study involving two measurement occasions approximately 13 months apart, utilizing data from the German Personality Panel with 404 young adults (69% female; on average 24 years old). We found that self-related core beliefs explained 18 % of the variance in life satisfaction over demographic variables and the Big Five (p < .001). Significant predictors were being optimistic vs. pessimistic, content, and trusting, accounting for most of the variance previously explained by Big Five traits. Results were largely replicated when controlling for initial levels of life satisfaction, indicating that self-related core beliefs also predict trajectories across time. We conclude that self-related core beliefs provide finer insights, compared to broad personality traits, to understand levels and change in life satisfaction. Given that beliefs can be modified through intervention, they may serve as a valuable starting point for enhancing life satisfaction.