On strongly monotone flows

M. Hirsch’s famous theorem on strongly monotone flows generated by autonomous systems u(t) = f(u(t)) is generalized to the case where f depends also on t, satisfies Carathéodory hypotheses and is only locally Lipschitz continuous in u. The main result is a corresponding Comparison Theorem, where f(t, u) is quasimonotone increasing in u; it describes precisely for which components equality or strict inequality holds.