Mental fortitude in everyday life: Associations between beneficial and harmful sisu, sisu-related states and affects, measured by ESM

This study explores how the Finnish concept of "sisu," denoting perseverance and inner strength in the face of adversity, manifests in the daily states. Moreover, the associations between beneficial and harmful sisu and positive and negative affectivity, which have implications for well-being and personality, were examined. Data was collected from 82 knowledge workers in four Finnish organizations, utilizing the Sisu Scale to assess beneficial and harmful sisu. Participants evaluated their sisu-related states and affectivity daily for three weeks using a mobile application. Multilevel modeling was employed to analyze the associations between sisu traits, sisu-related states, and affects, controlling for age and sex. Results indicate that high beneficial sisu is associated with increased determination, feelings of control, and positive affect. On the other hand, harmful sisu is linked to accepting overly challenging tasks, getting stuck on unproductive activities, and persisting in mundane tasks. High harmful sisu is also associated with decreased satisfaction and feelings of control. The findings illustrate how sisu manifests in everyday life, and indicate the significance of affective states in the expression of mental fortitude. It also seems that sisu plays a role in facing everyday challenges despite its traditional association with major adversities in the Finnish language. Further research is required to explore sisu-situation interactions and the role of negative affectivity in sisu.