In "The Reflex Arc Concept in Psychology" (1986), John Dewey gives a reconstruction of the reflex arc concept which forms the starting point of a "transactional paradigm" which is fundamental for all aspects of Dewey's work. In this article we start with a reconstruction of Dewey's paradigm. Next we show that Bowlby's attachment theory fits very well within such a transactional paradigm because it is based on ethology. A closer analysis, however, shows that the place of the mental in attachment theory is not completely consistent with the evolutionary assumptions of the transactional paradigm, and it is suggested that this problem can be solved from a Deweyan perspective.