Abstract
In this paper I discuss the role played by Ernst Mach on Nietzsche’s thought. Starting from the contents of his Beiträge zur Analyse der Empfindungen, I’ll show the close similarities between their view on both human knowledge and the scientific world description. In his writing on science Nietzsche shares Mach’s critique to the 19th century mechanism and its metaphysical ground, as much as his way of defining the substantial notions such as matter, ego and free will. Moreover, my investigation will make it clear that Mach cannot be seen as a direct source of Nietzsche’s thought, since the latter wrote many times on the same subjects long before his first reading one of his works. Rather, it is possible to consider the writings of Lange, Spir and Spencer as the first sources of Nietzsche’s views on the main themes Mach dealt with in his work from 1886.