ABSTRACT
Putnam, it’s best to immediately point out, always carefully prefaces his presentation of permutation arguments with a discussion of “operational” and “theoretical” constraints on reference. Theoretical constraints are (usually) a set of (axiomatizable) sentences fixed in truth-value and containing the terms in question. These constraints, as the discussion of the LöwenheimSkolem theorem and the humdrum theorem in § 2 showed, can do little by themselves to fix reference.
