Under what circumstances, if any, are we warranted to assert that a theory is true or at least approximately true? Scientific realists answer that such assertions are warranted only for those theories that enjoy explanatory and predictive success. A number of challenges to this answer have emerged, chief among them the argument from pessimistic meta-induction. According to this challenge, the history of science supplies ample evidence against realism in the form of successful theories that are now considered false. The main realist reaction to this challenge questions the legitimacy of the pessimistic meta-inductivist inference. Advocates of this approach argue that upon closer scrutiny the historical record can be reconciled with scientific realism. When a successful theory is abandoned, not all of its components are discarded but only those that are inessential or idle for the theory’s success. Their abandonment is thus inconsequential for the realist. So long as the essential components survive into the new theory there is no cause for alarm. More precisely, an outdated theory T which enjoyed some measure of success must, according to the realist, be: (i) partially true precisely because some of its theoretical claims are...