This introductory chapter of the study examines Aristotle's articulation of the question of being on the basis of a reading of book Zeta of the Metaphysics. Of the disparate texts collated under the title of Metaphysics, book Zeta is the first of what are held to be the three central books; central not only according to their situation within the text of the Metaphysics, but also, and much more significantly, in that they constitute one of the keystones of Aristotle's ontology. In reading book Zeta in relation to another of these keystones, namely the text of the Categories, the aim is to examine Aristotle's approach to the question of being with regard to Heidegger's attempts to destroy the traditional content of ancient ontology.