Abstract
The original version of the Principle of Verifiabüity (PV), formulated as "The meaning of a proposition is the method of its verification" (Schlick, quoting Wittgenstein), can be criticised as ungrammatical. Schlick's claim that it was a "truism" reflecting commonsense and scientific practice is refuted by PV's paradoxical consequences. Its users faüed to distinguish between operational and situational readings, the latter of which invokes a mythology of comparison with "facts". Wittgenstein rightly described PV as a "rule of thumb" of limited usefulness.