“Agentic fuel” and “Social dividends”: a mixed-methods explanatory study of optimism as a mediator between gratitude, mindfulness, and psychological wellbeing among Chinese university EFL students

These findings suggest that optimism is a key mechanism linking positive resources to wellbeing, though not exclusively. Mindfulness supports wellbeing by creating mental space for optimism, while gratitude operates dually, building optimism for future benefits and directly enhancing social-relational aspects of PWB in the present. Interventions should target these distinct mechanisms to optimize student wellbeing.