Thrasymachus’s Blush: The Science and Politics of Motivated Reasoning and ‘Principled Rhetoric’

1 " Thrasymachus conceded all these points, but not in the easygoing way I have just described. He had to be dragged every step of the way, sweating profusely, as you might expect in summer. This was the occasion when I saw something I had never seen before—Thrasymachus blushing. " Plato, Republic 350d For almost two millennia, philosophers were typically also the best social scientists of their day. For these thinkers, their descriptive psychology was designed from the beginning to serve as a logical base for their moral psychology, which served, in turn, to underwrite their ethical theory, and on to their political theory. And moving in the other direction, the descriptive psychology had to be compatible with, and preferably entailed by their epistemology and, in turn, their metaphysics and ontology. In short, these were often systematic thinkers whose work spanned the practical, the scientific, and the philosophical. Hobbes, for example, develops his psychology of the fear of violent death in the context of claiming that its burden makes anarchy intolerable and its universality makes sovereignty possible (Neblo, 2007). The rise of modern social science has created a necessary, and in many ways salutary, division of labor between philosophers and social scientists, driven primarily by the need for specialization in the face of technical advances. In addition, there has been an increasing sense that the different fields properly deal with fundamentally different phenomena. More specifically, since Max Weber, the distinction between intellectual inquiry regarding facts and values has loomed more salient. This is not to say that the two have proceeded in pristine isolation from each other. Many social scientists aspire to be practically relevant and regard their research as having important implications for normative theory and practice – " giving hands and feet to morality " in the words of one (Lasswell, 1941). Similarly, many philosophers question the sharpness of the divide, or at least believe that their conceptual apparatus should help nudge the social scientific research agenda, just like the normative category of " disease " guides medical research without compromising its scientific status. 2 And yet, because the division of labor has only intensified, the ability to manage good integration of normative philosophy and social science has become fraught with dead ends and positively harmful missteps in translation and transposition. In response, some social scientists fully embrace the fact-value dichotomy and disclaim any competence in the translation, …