Why does everybody say that classical Dirac's field has no physical meaning? This doesn't fully make sense to me. Why should classical EM field be more real than Dirac's field? The idea of a classical field describing electrons sounds like something that could be used to describe large number of electrons as a continuous matter. I'm absolutely certain, that you could of course approximate large number of electrons at least somehow as a continuous matter, but if we do so, would it be precisly the Dirac's field that we need for it?