 Paul Teller (2018) raises a different objection to the error-based conception of measurement accuracy. He argues against an assumption he calls “measurement accuracy realism”, according to which measurable quantities have definite values in reality. Teller argues that this assumption is false insofar as it concerns the quantities habitually measured in physics, because any specification of definite values (or value ranges) for such quantities involves idealization and hence cannot refer to anything in reality. For example, the concept usually understood by the phrase “the velocity of sound in air” involves a host of implicit idealizations concerning the uniformity of the air’s chemical composition, temperature and pressure as well as the stability of units of measurement. Removing these idealizations completely would require adding infinite amount of detail to each specification. As Teller argues, measurement accuracy should itself be understood as a useful idealization, namely as a concept that allows scientists to assess coherence and consistency among measurement outcomes as if the linguistic expression of these outcomes latched onto anything in the world. Precision is similarly an idealized concept, which is based on an open-ended and indefinite specification of what counts as repetition of measurement under “the same” circumstances (Teller 2013: 194).