People’s mood improves with their prospects of survival, utility and health and deteriorates with their loneliness. These mood-determinants are affected by the allocation of active-time to social interaction, learning, producing and consuming clean and dirty goods and exercising. In turn, people’s returns on these activities increase with their mood and people’s active time lengthens with their health. In addition to being improved by exercising and good mood, personal health is affected by the state of a commonly shared environment. An observed excessive personal production and/or consumption of dirty goods lowers the individual’s rate of return on social interaction. A two-directional relationship between loneliness, mood and, subsequently, health, active-time and survival is considered. The possibility of a vicious cycle is highlighted. Loneliness adversely affects mood and, in turn, the deterioration of mood adversely affects health and also intensifies loneliness as the mood-influenced return on interaction is diminished. The deterioration of health lengthens rest-time. The lower returns and the shortened active-time reduce interaction. The reduced interaction intensifies loneliness, and so on and so forth. Complexity prevents the derivation of optimal trajectories and strengthens the possibility of reliance on intuition. | Loneliness and survival of happiness seekers: A conceptualisation with mood-influenced returns on health-dependent active-time