Gibson's (1966Gibson's ( , 1979Gibson's ( /1986) ecological approach to perception, action, and cognition is patently non-representational and non-computational. In the place of these commonly assumed neural endowments, ecological psychology seeks to expose the laws that underlie intelligent capabilities. It is argued that this is the goal for understanding the directed behavior of not just humans, not just animals, and not just the living. We argue that an approach to intelligence that is physically grounded is completely consistent with-and is even a natural consequence ofthe central tenets of ecological psychology. We identify two dozen guidelines for seeking intelligence in first principles.Ask not what's inside your head but what your head's inside of (Mace, 1977, p. 43) The opening admonition provides an efficient summary of the strategy of ecological psychology. It stands as a call for the organism-environment system rather than simply the organism (or, even more narrowly, the brain or nervous activity) as the proper unit of analysis (e.g., J.