  Special relativity is reformulated as a symmetry property of space-time:
Space-Time Exchange Invariance. The additional hypothesis of spatial
homogeneity is then sufficient to derive the Lorentz transformation without
reference to the traditional form of the Principle of Special Relativity. The
kinematical version of the latter is shown to be a consequence of the Lorentz
transformation. As a dynamical application, the laws of electrodynamics and
magnetodynamics are derived from those of electrostatics and magnetostatics
respectively. The 4-vector nature of the electromagnetic potential plays a
crucial role in the last two derivations.
