Face recognition depends upon the uniqueness of each human face. This is accomplished by the patterns formed by the unique relationship among face features. Unique face-patterns are produced by the intrusion of random factors into the process of biological growth and development. Processes are described which enable a unique face-pattern to be represented as a percept in the visual sensory system. The components of the face recognition system are analyzed as is the manner in which the precept is connected through (...) microcircuits to a memory file so that the history of a perceiver’s encounters with a familiar face enables the perceiver to access a memory store that is a record of the outcome of past encounters with the perceived. The importance of the face recognition system in enabling humans to individuate members the social group is discussed, as well as the importance of face recognition in the development of the individual’s social identity and ability to be a collaborative member of the social groups to which it belongs. The role of prosopagnosia—the inability to recognize familiar faces—in furthering an understanding of the face recognition system is examined, as is its importance in demonstrating the crucial nature of face recognition in human social functions. It is proposed that human face recognition is not a unique phenomenon but is an elaboration of processes existing in nonhuman primates as well as in lower animals. (shrink)