  The technique for representing spinors and the definition of the discrete
symmetries is used to illustrate on a toy model properties of massless and
massive spinors states, in the first and the second quantized picture. Since in
this toy model the number of the starting massless representations is well
defined as well as the origin of masses and charges in $d=(3+1)$ space, this
contribution might help to clarify the problem about Dirac, Weyl and Majorana
kinds of representations in physically more interesting cases.
