This chapter examines the nature of ethics and economics as a single subject of investigation, and uses a complex systems approach to characterize the nature of that subject. It then distinguishes mainstream economic and social economic visions of it, where the former assumes that market processes encompass social processes, and the latter assumes that market processes are embedded in social processes. For each vision, strong and weak theses are compared. Both visions are first explained in terms of their respective views of the positive-normative distinction, then in terms of a central normative principle, and then in terms of their policy strategies. The chapter closes with comments on the future status of ethics and economics as a single subject of investigation.