In 1954, Sir Edmund Taylor Whittaker, an English mathematician and historian of science, credited Henri Poincaré with the equation E = m c 2 , and he included a chapter entitled The Relativity Theory of Poincaré and Lorentz in his book A History of the Theories of Aether and Electricity. He credited Poincaré and Lorentz, and especially alluded to Lorentz's 1904 paper (dated by Whittaker as 1903), Poincaré's St. Louis speech (The Principles of Mathematical Physics) of September 1904, and Poincaré's June 1905 paper. Whittaker attributed to Einstein's relativity paper only little importance, i.e., the formulation of the Doppler and aberration formulas. Max Born spent three years trying to dissuade Whittaker, but Whittaker insisted that everything of importance had already been said by Poincaré, and that Lorentz quite plainly had the physical interpretation.