In his paper “Five Kinds of Self-Knowledge,” Neisser (1988) reminds us of J. J. Gibson's (1979) argument that the self and environment are always coperceived. Gibson's discussion was mainly about what Neisser calls the ecological self, which is directly perceived. However, if, as Neisser has argued, the interpersonal self is also directly perceived, then the coperception of self and environment should occur on this level as well as on the level of the ecological self. If so, then while we engage in interactions with other persons, we perceive not only the other person but ourselves. What do we learn about the self in this way? I believe we learn about the self as actor in an environment inhabited by other humans: We learn how others react to us, how our actions influence the course of events, and whether our assumptions about the world, including ourselves, are correct.

Neisser makes the further, and very important, point that the perception of the interpersonal self must be in species-specific terms: “The successful achievement of intersubjectivity depends not only on the operation of the perceptual and motor systems, but on some additional, specifically human mechanism that permits us to relate to members of our own species” (1988, p. 12).