Behaviour plays an important role in advancement of sustainable development. It is a classical social dilemma of what is common good in long run is not necessarily the best for individual utility maximization. Reassuringly, individuals are increasingly concerned with sustainability and are highly aware of environmental impact of their own behaviours. But there lies a discrepancy in actual behaviours and the intended concern for environment. The discrepancy has attracted researches from diverse scientific disciplines. The paper explores the importance of individual over group by traversing through theoretical paradoxes.