The paper sets an agenda for `institutional economics as a moral science' (IEMS) by understanding the micro-macro links humans and institutions mutually construct, relying on the writings and thinking of the Cambridge School. We argue that economics should be reconsidered as a study of man with particular emphasis on human nature and the dynamics of institutions. We urge scholars of mainstream economics, who have minimised non-ergodicity and uncertainty and exaggerated utilitarianism, to have cooler heads and warmer hearts. This implies that we need to strike a right balance between economics and ethics by bringing the man as she/he is back into the positivist approach of mainstream economics and by enriching the ethical approach of economics as a moral science. We hope for a revival of the Cambridge School as a moral foundation for economics in the twenty-first century.