Families from spinors

The possible utility of spinor representations of large orthogonal internal-symmetry groups is explored. The repetitive structure of families is incorporated quite naturally, but there is a difficulty with extra "conjugate" families having $V+A$ weak currents. Possible methods for removing these conjugate families from the low-energy spectrum are discussed. An SO(18) example is discussed in some detail. An occurrence of spinors as a classification of composite particles is discussed. A long appendix discusses useful techniques for practical calculations involving spinors.