  String theorists are certain that they are practicing physicists. Yet, some
of their recent critics deny this. This paper argues that this conflict is
really about who holds authority in making rational judgment in theoretical
physics. At bottom, the conflict centers on the question: who is a proper
physicist? To illustrate and understand the differing opinions about proper
practice and identity, we discuss different appreciations of epistemic virtues
and explanation among string theorists and their critics, and how these have
been sourced in accounts of Einstein's biography. Just as Einstein is claimed
by both sides, historiography offers examples of both successful and
unsuccessful non-empirical science. History of science also teaches that times
of conflict are often times of innovation, in which novel scholarly identities
may come into being. At the same time, since the contributions of Thomas Kuhn
historians have developed a critical attitude towards formal attempts and
methodological recipes for epistemic demarcation and justification of
scientific practice. These are now, however, being considered in the debate on
non-empirical physics.
