What are you, really? To the rest of the world you appear as a particular human being, a publicly observable organism with a complex biological and social history and a name. But to yourself, more intimately, you appear as ‘I’, the mental subject of your experiences, thoughts, feelings, memories and emotions. This inner self is only indirectly observable by others, though they ordinarily have no doubt about its existence, as you have no doubt about their inner lives. One of the enduring questions of philosophy is whether there really is such a thing as the self, and if so, what it is. Descartes famously thought that it was the thing of whose existence he could be most certain, even if he doubted the existence of the physical world and therefore of the human being called René Descartes – because in thinking, he was immediately aware of his own existence as the subject of his thought. Others have argued that this idea of the self is an illusion, due to a misunderstanding of how the word ‘I’ functions: in fact it refers to the human being who utters it, and it is you the publicly observable human being, and not anything else, that is the subject of all your experiences, thoughts and feelings. Galen Strawson’s book Selves, a work of shameless metaphysics, argues that selves exist and that they are not human beings.
more from Thomas Nagel at the LRB here.