An embodiment of the present invention is a system for identifying a user by observing irregularities on the surface of an eyeball of the user includes a topography system and a gaze tracking system. The topography system obtains one or more discernable features of the eyeball and stores the one or more discernable features. The gaze tracking system observes the irregularities, compares the irregularities to the one or more discernable features, and identifies the user if the irregularities and the one or more discernable features match.