An important epistemological lesson can be learned from the impossibility to determine the one-way velocity of light and the immediate implication that simultaneity is conventional. The vicious circle -- to determine whether two distant events are simultaneous we need to know the one-way velocity of light between them, but to determine the one-way velocity of light we need to know that the two events are simultaneous -- is an indication of the need for a profound change of our view on (...) reality. (shrink)

The special theory of relativity is widely regarded as the primary threat to the otherwise intuitive presentist worldview. In particular, both the relativity and conventionality of simultaneity within STR appear to undermine presentism and support eternalism. However, the single term ‘simultaneity’ describes multiple potentially independent concepts. By establishing the mutual independence of the relevant concepts of simultaneity, the presentist and eternalist may agree to move past the initial threat to presentism posed by STR. The subsequent debate hinges on whether presentism (...) or eternalism best accounts for the principle of relativity. The presentist is often accused of initially failing to identify the absolute present and then constructing a model that hides it using an unlikely set of premises. As a result, the eternalist Minkowski space-time interpretation appears simpler in many respects. However, it is demonstrated that on presentism one may obtain the principle of relativity by simply prohibiting instantaneous signals between distant events. Many of the objections against the presentist Neo-Lorentzian interpretation of STR are answered in light of this demonstration. The partition between the experimental evidence provided by STR and human experience is found to be unnecessary. (shrink)