AbstractMany of the foundational theoretical ideas in the field of learning and memory are traced to Donald Hebb. Examination of these ideas and their evolution suggest that Karl Lashley might have significantly influenced their development. Here, we discuss the relationship between Hebb and Lashley, and the parallels between them. Many now investigating the neurobiological basis of memory may be unaware both of Hebb's original descriptions, and the likely substantial contributions of Lashley. Many of their concerns remain with us today, and by clarifying the history we hope to strengthen the foundations of our field.