Whereas Newton had maintained that colours already exist blended together in sunlight, Goethe insisted that they arise from the conjunction of polar opposites—just look, he said, at the coloured fringes you see against a sharp black/white edge. ...Many Romantic experimenters (including Samuel Coleridge, an important conduit for Naturphilosophie into Britain) welcomed Goethe's emphasis on polarity, which resonated with their own investigations into magnetic, electrical, and chemical activity—north and south, positive and negative, attractive and repulsive. Just as Goethe used his own eye as a recording instrument, they made their own bodies part of electric circuits.
Johann Wolfgang von Goethe