The central argument for functionalism is the so-called argument from multiple realizations. According to this argument, because a functionally characterized system admits a potential infinity of structurally diverse physical realizations, the functional organization of such systems cannot be captured in a law-like manner at the level of physical description (and, thus, must be treated as a principally autonomous domain of inquiry). I offer a rebuttal of this argument based on formal modeling of its premises in the framework of automata theory. In this formal model I exploit the so-called minimal (universal) realizations of automata behaviors to show that the argument from multiple realizations is not just invalid but is refutable, in the sense that its premises (when made formally precise) entail the very opposite of the functionalist's conclusion.