= Solution
\b[Zero stationary <isolating integrals> are possible when time dependence removes <conservation of energy> and no other symmetry or invariant survives.] For instance, a generic time-dependent nonsymmetric <gravitational potential> need not have a stationary integral. This is not possible in an ordinary time-independent galactic <gravitational potential>: $E=\tfrac12v^2+\Phi$ is already an <isolating integral> on a regular <specific orbital energy> surface. An explicitly time-dependent constant that encodes an initial condition does not contradict the stationary count.
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