80 SOCIAL SCIENTIST
(5) The second paper on special relativity, containing the E==MG2 relation, received September 27.
(6) A second paper on Brownian motion, received December 19.
The June 1905 paper on the electrodynamics of moving bodies consists of 10 sections after the first five of which the special theory of relativity is obtained in a finished form. Pais discusses the background of developments in physics of the period 1895-1905, the role of various scientists like Lorentz, Poincare, Fitzgerald and the status of the Michelson-Morey experiment and concludes: "Lorentz transformations had been written down. Simultaneity had been questioned. The velocity of light as a limiting velocity had been conjectured. But prior TO 1905 there was no relativity theory" (p 128).
The relativity theory, based on two postulates, namely, that the laws of physics take the same form in all inertial systems and that the velocity of light is the same wliether light be emitted by a body at rest or by a body in uniform motion showed that "space-time is not necessarily something to which one can ascribe a separate existence, independently of the actual objects of physical reality" (A E).
Of the three names linked with the theory of relativity, those of Lorentz, Poincare and Einstein, Pais has the following poignant and well documented comment:
"In 1905 Einstein and Poincare stated independently and almost simultaneously (within a matter of weeks) the group properties of Lorentz transformations and the addition theorem of velocities. Yet, both Lorentz and Poincare missed discovering special relativity; they werr too deeply steeped in considerations of dynamics. Only Einstein saw the crucial new point; the dynamic ether must be abandoned in favour of a new kinematics based on two new postulates. Only he saw that the Lorentz transformations, and hence the Lorentz-Fitzgerald contraction, can be derived from kinematic arguments. Lorentz acknowledged this and developed a firm grasp of special relativity, but even after 1905 never quite gave up either the ether or his reservations concerning the velocity of light as an ultimate velocity. In all his life, Poincare never understood the basis of special relativity" (p 21).
Special Relativity led to new modes of philosophical reflection, though Pais does not consider it revolutionary in the sense in which quantum concepts are, for he rightly considers that relativity "turned Newtonian mechanics and classical chemistry into approximate sciences, not diminished but better defined in the process" (p 163).
In an interesting chapter titled "The Edge of History", Pais makes an incisive analysis of Einstein's relationship with and attitude to his contemporaries who were his precursors, Lorentz and Poincare. While Einstein considered Lorentz to be a most well rounded and Harmonious personality, his attitude to Poincare is characterised by what may be termed petulance or professional envy(?). Pais's historical