The vagueness of authenticity in 'Being and Time' (Martin Heidegger)

The purpose of the present project is to show the manner in which Early Heidegger's notion authenticity is vague. We cannot, given the rest of Heidegger's ontology of Dasein in Being and Time, tell what counts as a case of authentic, rather than inauthentic existence. The first half of the present work is devoted to carefully explaining some relevant, general features of Dasein's ontology, followed by an explanation of the structures associated with authenticity. In the third chapter I defend Heidegger's account of authenticity and, in the process, my own interpretation of his account. In the final chapter I argue in favor of my main claim that Heidegger's notion of authenticity is vague in nature and that a case of a particular, authentic Dasein cannot be definitively derived.