A Dirac-like inference of Maxwell's equations

The purpose of this article is to present an elementary derivation of Maxwell's equations suitable for an opening lecture in a modern applied electromagnetism course. It is inspired by Dirac and the way he inferred his celebrated equation. Interestingly enough, his arguments, which are gradually fading away from modern quantum field theory courses, regain their vitality in the context of classical electrodynamics. Consequently, this derivation starts with (1) the wave equation and leans on (2) the Huygens principle and (3) transversal polarization of light as an electromagnetic wave. All three ingredients are firmly rooted among the experimental facts.