 To be sure, there are important differences between arithmetic and rational behavior. The objects of arithmetic, numerals and the numbers they refer to, are relatively clear cut, whereas the objects of rational behavior vary even when the same theoretical machinery is used. Return to expected utility theory as an example. An agent may be viewed as deliberating over options with the aim to choose one that maximizes his personal welfare, or viewed to act as if he deliberately does so without actually doing so, or understood to do nothing of the kind but to instead be a bit part player in the population fitness of his kind.