– 1 – Dimensions of Objectual Understanding Christoph Baumberger, ETH Zurich, Christoph.Baumberger@env.ethz.ch Georg Brun, University of Berne, Georg.Brun@philo.unibe.ch Abstract In science and philosophy, a relatively demanding notion of understanding is of central interest: an epistemic subject understands a subject matter by means of a theory. This notion can be explicated in a way which resembles JTB analyses of knowledge. The explication requires that the theory answers to the facts, that the subject grasps the theory, is committed to the theory and justified in the theory. In this paper, we focus on the justification condition and argue that it can be analysed with reference to the idea of a reflective equilibrium. 1. Introduction A relatively demanding form of understanding is of central interest in science and philosophy. We strive to understand climate change through climate models, issues in medical ethics by means of a system of ethical principles, or a financial crisis with the help of economic theories. In all these examples, we seek not only a single explanation of a phenomenon, but strive to understand a subject matter (or “domain” or “topic”) by means of a theory. This we call “objectual understanding”. 1 Recent debates about the nature of understanding have mostly been focused on explanatory rather than objectual understanding. 2 As a consequence, not only have the conditions for ascribing objectual understanding not been analyzed sufficiently, but the very notion of objectual understanding has remained somewhat unclear. It is therefore not surprising that some authors are skeptical whether there is a genuine phenomenon of objectual understanding as opposed to other forms of understanding and knowledge (cf. Khalifa 2013). Only two influential accounts have been proposed up to now. Since Kvanvig (2003; 2009) does not discuss the role of theories as means of understanding, we rather take Elgin’s (e.g. 1996; 2006) account as a starting point and assume that objectual understanding is a distinctive form of understanding. The goal of this paper is to systematically explore the various dimensions of objectual understanding. In particular, we develop an explication 3 of the notion of objectual understanding. This calls for stating conditions which capture key features of our ordinary use of “understanding” in relevant contexts. And the resulting conception should be suitable for some of the roles philosophers have assigned to the notion of understanding. Such roles include making sense of science in general (Elgin 2006; de Regt et al. 2009) and of explanation in particular (Friedman 1974; Grimm 2010), avoiding the value problem for knowledge (Kvanvig 2003; Pritchard 2010; Grimm 2012), identifying intellectual virtues (Zagzebski 2001; Riggs 2003) and characterizing morally worthy action (Hills 2010). Discussing such applications of our proposal, however, lies outside the scope of this paper. In: Stephen Grimm, Christoph Baumberger, and Sabine Ammon (eds). Explaining Understanding. New Perspectives from Epistemology and Philosophy of Science. New York: Routledge.