Something apparently has to give. A version of (S3) strong enough to license (R3)
seems incompatible with the fact that many successful theories contain nonreferring
central terms. But any weakening of (S3) dilutes the force of, and removes the rationale
for, the realist's claims about convergence, retention, and correspondence in inter-
theory relations." If the realist once concedes that some unspecified set of the terms
of a successful theory may well not refer, then his proposals for restricting "the class of candidate theories" to those that retain reference for the prima facie referring terms in earlier theories is without foundation.