Striving and happiness: Between- and within-person-level associations among grit, needs satisfaction and subjective well-being

Accumulating evidence suggests that grit - perseverance and passion for long-term goals - facilitates subjective well-being (SWB), yet the underlying mechanism and the time frame in which this effect operates are less known. Building upon self-determination theory, we propose that needs satisfaction (NS) acts as a key mediator of the effect of grit on SWB. Study 1 comprised a cross-sectional survey of 2,963 adolescents and found that, at the dispositional level, grit was positively associated with SWB, and NS played a mediating role. Study 2 further uncovered the intrapersonal dynamics of the relations among grit, NS and SWB with a 21-day diary study (N = 78). Multilevel within-subject mediation analysis showed that daily grit promoted happiness by satisfying basic psychological needs. Moreover, this effect was observed regardless of the participants' trait-level grit. Collectively, our findings highlighted the importance of NS in explaining the association between grit and SWB regarding the inter- and intrapersonal relations.