  Impressed by the initial success of Dirac’s equation of the spinning  electron within the special relativistic context, Weyl adapted  Dirac’s special relativistic theory of the electron to the general  theory of relativity in three groundbreaking papers (Weyl  (1929b,c,d)). A complete exposition of this formalism is presented in (Weyl (1929b)). O’Raifeartaigh (1997) says of this paper: 