  Now I come to another piece of work of Weyl’s which dates back to  1929, and is called Weyl’s two-component neutrino theory. He invented this theory in 1929 in one of his very important articles … as a mathematical possibility satisfying most of the requirements of  physics. But it was rejected by him and by subsequent physicists  because it did not satisfy left-right symmetry. With the realisation  that left-right symmetry was not exactly right in 1957 it became  clear that this theory of Weyl’s should immediately be re-looked at.  So it was and later it was verified theoretically and experimentally  that this theory gave, in fact, the correct description of the  neutrino.