Why is "generation number" or "family number" conserved among leptons, but not among quarks? Why does a positive kaon decay into an antimuon and a muon neutrino? Why doesn't it decay into an antimuon and an electron neutrino? The anti-strange (generation 2) flavor then becomes anti-muon flavor, while the up flavor (generation 1) becomes electron (neutrino) flavor. Has the neutrino flavor ever been tested in kaon decays? What would the Feynman diagram look like? I'd imagine that the quark and antiquark become a W+, which then decays into the lepton-antilepton pair. Somehow the W+ must carry a "generation" quantum number... "Does the strangeness lose its flavor (on the bedpost overnight...)"