where ψ is a spinor field now with infinitely many components, irreducible to a finite number of tensors or spinors, to remove the indeterminacy in sign. The matrices α and β are infinite-dimensional matrices, related to infinitesimal Lorentz transformations. He did not demand that each component of 3B satisfy equation (2); instead he regenerated the equation using a Lorentz-invariant action, via the principle of least action, and application of Lorentz group theory.