Fortunately, there’s another way. First synchronize two clocks A and B at rest with respect to each other as follows: Reflect a photon back and forth between A and B, divide the lapsed time for its round trip in two, and that’s the event on A (B) that is simultaneous with the reflection at B (A) and thus ‘the present’ for the A-B system. Now we’re ready to try synchronizing clocks A and C in relative motion. We just repeat the process above using the same photons but this time letting some photons reflect off B and some go on to reflect off clock C; then all return to A. The stunning result, however, is that the A-C ‘present’ differs from the A-B ‘present’. The "downfall of the present" is complete.