 Realists might wish to endorse the EPR criterion as an idealized test for the mind-independent reality of (macro-)physical quantities — even if we rarely (if at all) are able to “predict with certainty” the outcome of an experiment, we can, some would argue, approach near-certainty in a significant class of cases without disturbing the system. Carnapian anti-realists, however, will deny the EPR criterion validates any external notion of mind-independent existence, regarding it instead as a means of settling internal existence questions about physical quantities.