I know we have discussed this recently, but I would like to stir the pot again.
Serway and Beichner (5/e) on page 1035 ask the following questions:
"Consider this thesis: 'Joseph Henry, America's first professional
physicist, changed the view of the Universe during a school vacation at the
Albany Academy in 1830. Before that time, one could think of the Universe
as consisting of just one thing: matter: In Henry's experiment, after a
battery is removed from a coil, the energy that keeps the current flowing
for a while does not belong to any piece of matter. This energy belongs to
the magnetic field surrounding the coil. With Henry's discovery of
self-induction, Nature forced us to admit that the Universe consists of
fields as well as matter.' What in your view constitutes the Universe?
Argue for your answer."
and
"Discuss the similarities and differences between the energy stored in the
electric field of a charged capacitor and the energy stored in the magnetic
field of a current-carrying coil."
Most of my students voted that fields are real, whatever "real" means.