1688-1757

French physicist and leading opponent of Newtonianism. Most French scholars, with Castel at their head, viewed Isaac Newton's reliance on experimentation and observation as particularly undesirable, preferring instead the a priori, rationalistic approach of René Descartes. Castel published an anti-Newtonian theory that delayed acceptance of Newton's ideas and contributed greatly to the relative stagnation of French research. Castel is also known for his ocular harpsichord, which generated corresponding colors and musical tones.