In our historical survey we come next to the researches of Faraday and
Maxwell. Faraday was convinced that if electrical processes are
accompanied by magnetic forces, as Oersted had shown, the reverse must
also be true - magnetism must be accompanied by electricity. He was led
to this correct conviction by his belief in the qualitative unity of
all the forces of nature - a reflexion, as his biography shows, of his
strongly monotheistic, Old Testament faith. Precisely this view,
however - which since Faraday natural science has quite consciously
adopted as a leading principle - will reveal itself to us as a
fundamental error.

It seems paradoxical to assert that the more consistently human thought
has followed this error, the greater have been the results of the
scientific investigation of electricity. Precisely this paradox,
however, is characteristic of the realm of nature to which electricity
belongs; and anyone earnestly seeking to overcome the illusions of our
age will have to face the fact that the immediate effectiveness of an
idea in practice is no proof of its ultimate truth.

Another eloquent example of the strange destiny of human thought in
connexion with electricity is to be found in the work of Clark Maxwell,
who, starting from Faraday's discoveries, gave the theory of
electricity its mathematical basis. Along his purely theoretical line
of thought he was led to the recognition of the existence of a form of
electrical activity hitherto undreamt of - electro-magnetic vibrations.
Stimulated by Maxwell's mathematical conclusions, Hertz and Marconi
were soon afterwards able to demonstrate those phenomena which have led
on the one hand to the electro-magnetic theory of light, and on the
other to the practical achievements of wireless communication.