The role of learning in cognitive development has been conceptualized in three different ways. From a purely empiricist perspective, cognitive development is learning. A general-purpose learning process—association formation—is the process through which the structure of experience forms the structure of the mind. The only developmental constraints on knowledge acquisition are whether the capacity to form associations between elementary sensations, or between sensations and responses, is in place. If one’s sensory systems are immature or not functioning, or the capacity to form associations is weak, then little or no cognitive development can occur. The structure of the associative learning process is independent of the structure of the material being learned. There are no a priori data-organizing principles. The mind of the infant is a blank slate (tabula rasa), and “The senses at first let in particular ideas, and furnish the yet empty cabinet....”(p. 72; Locke, 1690). The same learning process operates throughout development and for all domains of understanding. This assumption is shared by a range