Maxwell, James Clerk (1831–79)

For his two achievements of unifying electricity, magnetism and light, and of inventing statistical dynamics, Maxwell stands as the founding mind of modern theoretical physics. More than any other physicist’s his also was a mind shaped and informed by a training in philosophy, even though, unlike Heinrich Hertz or Ernst Mach, for example, he never wrote a philosophical treatise. Therein lies the point, however. Mach’s and Hertz’s best discoveries seem remote from their metaphysics, Maxwell’s are bound up with his. Particularly important philosophically are his interconnected uses of relation, analogy and classification. He is also responsible for introducing the word ‘relativity’ into physics, and for articulating the scientific problematic that led to Einstein’s theory.