This paper argues that agent-based modeling’s innovations in method developed in terms of simulation techniques also involve an innovation in economic methodology. It shows how Epstein’s generative science conception departs from conventional methodological reasoning, and employs what I term an open rather than closed approach to economic methodology associated with the roles that reflexivity, counterfactual reasoning, and abduction play in ABM. Central to this idea is that improvements in how we know something, a matter of method, determine whether we know something, a matter of methodology. The paper links this alternative view of economics and economic methodology to a social science model of economics and contrasts this with standard economics’ natural science model of economics. The paper discusses what this methodological understanding implies about the concept of emergence.