Abstract

This note discusses the fact that the Second Postulate in the Special Theory of Relativity (STR) is an absolute statement which implicitly acknowledges, despite the claim in [3] to the contrary, the existence of what was known as ?ether?. The stated absolute property of light to have a ?definite velocity c independent of the emitting body? implicitly requires, especially from the point of view of the stationary observer, propagation of light to occur in an ubiquitous absolute medium external to any system (ether). If the outcome of the Michelson-Morley experiment is null, as is widely accepted, then it is an experiment rejecting the Second Postulate, respectively, disproving STR.