Brian Epstein

In recent years, the project of providing microeconomic foundations for macroeconomics has taken on new urgency. Some philosophers and economists have challenged the project, both for the way economists actually approach microfoundations and for more general anti-reductionist reasons. Reductionists and anti-reductionists alike, however, have taken it to be trivial that the macroeconomic facts are exhaustively determined by microeconomic ones. In this paper, I challenge this supposed triviality. I argue that macroeconomic properties do not even globally supervene on microeconomic ones. This is simply a consequence of the difference in the explanatory goals of the respective fields, which implicitly carve out the microeconomic property set in such a way that it underdetermines macroeconomic properties. It means, however, that microeconomics-based foundations for macroeconomics are inadequate in principle.

Are the standards of reasoning and rationality in divination, religious practice, and textual exegesis different from those in the sciences? Can there be different standards of reasoning and rationality at all? The intense “rationality debate” of the 1960s, 70s, and 80s focused on these questions and the related problems of relativism across cultures and systems of practice. Although philosophers were at the center of these debates at the time, they may appear to have abandoned the question in recent years. On the contrary, I discuss recent developments in philosophy that approach the issue from a number of new directions, changing our understanding of reasoning and rationality. I argue that, in comparing the diviner to the scientist, focusing on reasoning is likely to be a red herring. Instead, I argue that a careful treatment of rationality, paying particular attention to its context-dependence, untangles longstanding confusions. Moreover, it points the way forward to investigating modest but interesting ways for there to be alternative standards of rationality.

The thesis of methodological individualism in social science is commonly divided into two different claims—explanatory individualism and ontological individualism. Ontological individualism is the thesis that facts about individuals exhaustively determine social facts. Initially taken to be a claim about the identity of groups with sets of individuals or their properties, ontological individualism has more recently been understood as a global supervenience claim. While explanatory individualism has remained controversial, ontological individualism thus understood is almost universally accepted. In this paper I argue that ontological individualism is false. Only if the thesis is weakened to the point that it is equivalent to physicalism can it be true, but then it fails to be a thesis about the determination of social facts by facts about individual persons. Even when individualistic facts are expanded to include people’s local environments and practices, I shall argue, those still underdetermine the social facts that obtain. If true, this has implications for explanation as well as ontology. I first consider arguments against the local supervenience of social facts on facts about individuals, correcting some flaws in existing arguments and affirming that local supervenience fails for a broad set of social properties. I subsequently apply a similar approach to defeat a particularly weak form of global supervenience, and consider potential responses. Finally, I explore why it is that people have taken ontological individualism to be true.

This paper presents a systematic approach for analyzing and explaining the nature of social groups. I argue against prominent views that attempt to unify all social groups or to divide them into simple typologies. Instead I argue that social groups are enormously diverse, but show how we can investigate their natures nonetheless. I analyze social groups from a bottom-up perspective, constructing profiles of the metaphysical features of groups of specific kinds. We can characterize any given kind of social group with four complementary profiles: its “construction” profile, its “extra essentials” profile, its “anchor” profile, and its “accident” profile. Together these provide a framework for understanding the nature of groups, help classify and categorize groups, and shed light on group agency.