Explaining person identification: an inquiry into the tracking of human agents.

To introduce the issue of the tracking and identification of human agents, I examine the ability of an agent ("a tracker") to track a human person ("a target") and distinguish this target from other individuals: The ability to perform person identification. First, I discuss influential mechanistic models of the perceptual recognition of human faces and people (the face-recognition program). Such models propose detailed hypotheses about the parts and activities of the mental mechanisms that control the perceptual recognition of persons. However, models based on perceptual recognition are incomplete theories of person identification because they do not explain several identification behaviors that are fundamental to human social interactions (e.g., identifying unobservable persons and imposters). Furthermore, recognition-based models tend to appeal to the controversial concept of the "identity" of a person without explaining what determines personal identity and persistence. To overcome these limitations, I propose to integrate the face-recognition program into a broader causal-historical theory of identification. The causal-historical theory of identification complements models focused on perceptual recognition because it can account for the types of non-perceptual identification overlooked by the face-recognition program. Moreover, it can decompose the identification behaviors into tracking processes that succeed or fail to be sensitive to causal characteristics of a target. I illustrate these advantages with a discussion of the difference between the tracking of a person understood as either a causally continuous biological organism (organism-based tracking) or a psychologically continuous mind (psychological tracking). Finally, I argue that the causal-historical theory provides a theoretical framework for investigating the tracking of relations between a target and its contextual and historical attributes, such as a target's possessions.