 The correspondence principle can be understood broadly to mean that as a quantum system system is scaled up to macroscopic size, its behavior should become more like a classical system. Alternatively, the behavior of a quantum model should reproduce the behavior of macroscopic classical models in the limit of large quantum numbers. The correspondence principle is sometimes conceived as letting Planck’s constant go to zero. Nevertheless, all these conceptions are terribly inadequate. Since \(h\) is a constant of nature, it can never change value, much less go to zero. One always has to speak of relevant limits of ratios of the classical to quantum actions, for example, which always involve Planck’s constant. Moreover, these limits are singular, meaning that the smooth behavior of a quantity or pattern is disrupted, often by becoming infinite (Friedrichs 1955; Dingle 1973; Primas 1998). So there is no straightforward sense in which quantum models become increasingly similar to macroscopic systems as quantum numbers get large. 