Special relativity and the conventionality of simultaneity

The concept of intrasystematic simultaneity of distant events is considered. The non-empirical nature of the concept of intra-systematic simultaneity is generally attributed to the fact that distant clocks must be physically synchronized before one way velocities can be measured. Since all such synchronization procedures have traditionally been thought to involve interpoint signalling processes all criteria for establishing distant simultaneity seemed to be based upon logically circular reasoning. The aim of this essay is to dispel this notion of a fundamental circularity inherent in the concept of intra-systematic simultaneity. Several logically independent synchronization methods are discussed which do not already presuppose prior knowledge of one way velocities. Hence the concepts of intra-systematic simultaneity and one-way velocity are vindicated as non-circular, empirically meaningful, and no more than trivially 'conventional'.