Abstract

In Part One of Beyond Good and Evil Nietzsche writes that anyone who believes in “immediate certainties” such as “I think” encounters a series of “metaphysical questions”. The most important of these “problems of intellectual knowledge” concerns the existence of an ‘I’, as much as our believing it to be the cause of thinking. Therefore, any remark about our mental faculties directly follows from our defining what we could call the basic psychical unity, i.e. our view on higher-level psychical functions is strictly related with the properties we attribute to the notion of ‘I’. As we know, the main ideas on this subject that Nietzsche states in his book from 1886 come from the neo-kantian views of Lange, Spir and Teichmüller, and we cannot forget the important (even if hidden) reference to Lichtenberg in § 17 of the same work. Nevertheless, Nietzsche seems to move beyond all these sources, and in many of his writings we can find a new definition of the ‘ego’, finally free from any reference to a thing in itself, and for this reason closer to the ideas of the Austrian scientist Ernst Mach. In this paper I shall carry these remarks out. I’ll show the main properties of the notion of ‘I’ Nietzsche concerns with in his writings and, therefore, the grounds of his view on the mind-body problem. Moreover, I will argue that, once we observe that Nietzsche looks at the ‘ego’ as a mere regulative fiction having no ontological value out of the chain of sensation and representation it brings together, we could find out the close similarity with the way Mach defines it in his Beiträge zur Analyse der Empfindungen (1886). This reference could help us to understand in a better way some statements Nietzsche wrote in his notebooks, and, secondly, to show how strictly was his philosophy of mind related with the main outcomes of 19th century science. Indeed, Nietzsche’s refusal of the belief “that there must necessarily be something that thinks” ‒ a view that results from the anti-metaphysical intent leading his naturalism ‒ seems to be one of the most important assumptions of the new born physiological psychology, an idea out of which many of the 20th century philosophical debates arose.