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.