  In this paper we discuss the ontology of flavor states of oscillating
neutrinos. While an heuristic approach to this subject, experimentally
successful in the high energy regime, is generally adopted, a logically
consistent definition of flavor states describing neutrinos produced and
detected in weak processes is still desirable and essential from a theoretical
perspective. Here we briefly review basic facts and present some arguments
which suggest that the definition of flavor states as eigenstates of flavor
charges is the most reasonable one.
