Heidegger's lecture course of the summer semester of 1925, the text of which is now available as the History of the Concept of Time,¹ is justifiably described as an early draft of Being and Time. As such, the status of this work, its hermeneutical import, is somewhat ambiguous. As the text of a lecture course not originally intended for publication, it would seem to lack a certain critical authority. Viewed as a "draft," it would apparently have to stand under the shadow of its final, definitive appearance, the text of Being and Time itself. For Heidegger specialists, of course, this text has great significance. Questions about conceptual development and terminology, about shifts in meaning and emphasis, the apparently non-existential tone of the lectures, all cast light on the understanding of Heidegger's development.