While the parallels between habit and identity seem obvious, namely, mainly, that they both require consistency over time and that they are plastic, a theory that explicitly and systemically relates habit to identity has not yet been developed. The current essay is an initial reflection in this direction. It answers the question whether and how habit and, its complement, neuroplasticity can account for an innovative conception of identity. First it is shown that, within a person, psychological phenotypes and neurological make-up are inextricably intertwined, to, then demonstrate that the whole of these intertwinements within a person determines mental identity. Now, something has become integrated into identity if it is traceable to a certain point in the past, so that a singular deviating action is not part of one’s identity. After a while, after having performed an act long enough, so that it has become etched in the neuronal system by a plastic process and, thus, has become habitual, it will also have become a part of mental identity. Logically, mental identity is the sum of all habits. Finally, considering this is merely an initial reflection, some difficulties are discussed.