The article is divided in three main parts. The first part shows that the first three chapters of the second essay of On the Genealogy of Morality (1887) give a genealogical account of the emergence of reason in human history, and that this account involves the claim that reason is a development of human engagement with social rules: Nietzsche understands the emergence of reason as the emergence of a normative space of reasons. The second part interrogates Nietzsche's conception of value, purpose, and meaning in order to show that he is not a proponent of any version of "bald naturalism": he does not equate what is "really real"with a natural world of causation devoid of value, purpose, and meaning. The third part of the article shows that, although Nietzsche's perspectivism does not assign to the space of reasons the status of a purely autonomous realm of justification, he does not dismiss rational normativity, or the space of reasons, as merely illusory. Nietzschean genealogy is shown to be a reflective questioning of our values that investigates the reasons behind our deeper normative commitments.