2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/39892A solution to the generation puzzle based on a nonabelian generalization of electric-magnetic duality is briefly reviewed. It predicts 3 and only 3 generations of fermions and explains the hierarchical mass spectrum as well as the main features in both the quark and lepton mixing matrices. A calculation to leading perturbative order already gives reasonable values to about half of the Standard Model parameters.6 pages, uses ws-p8-50x6-00.cls, invited talk at APPC 2000 TaipeiHigh Energy Physics - Phenomenologytext