The aim of the article is to show how mirror neurons, a recent discovery in neurology, might play a vital role in the creation of unity in our lives. This unity is a formal one. But since we all share the illusion that there is more to personal identity than only a formal unity, and that deep in ourselves the inner essence of our true self (Soul) lies hidden, this same mechanism should also be able to shed some light on the inescapability of this illusion. I begin by elaborating on the parallel Wittgenstein saw between the problem of the Self and the problem of mental processes. I continue by focusing on the problem of mental processes, first by looking at the philosophy-of-mind-debate where the understanding of the other is studied, then by looking at developmental psychology studies of how a child understands itself. With the help of Sartre's being-for-the-other, the conclusion will lead us to the formal unity in our lives that Wittgenstein described with his limit-concept.