Dan Sperber's recent formulations of Rationalism advocate a form of cognitive reductionism in the interpretation of "apparently irrational beliefs" that is contingent upon a linear model of brain functioning analogous to the operations of a computer. This paper considers several nonexistent beings among the Chipewyan, arguing that such reductionism is invalid. As shared forms, their meaning is consistently indeterminate and temporally nonlinear, invalidating the assumptions of a Rationalist approach.