 Is there some independent way to validate Lewis’s distinction? Michael Resnick thinks so [Resnick 1987]. Putnam maintained that \(M\), the model he constructs of the ideal theory \(T\), is an intended model because it passes every operational and theoretical constraint we could reasonably impose. It passes every theoretical constraint, he argues, simply because it makes every thesis of \(T\) true. But unless the Reflection Principle (RP) below holds, Resnick argues, this inference is just a non-sequitur: