The extensive volume 80 of the complete edition with the title Lectures as defined by Martin Heidegger was divided into two volumes. The first volume includes ten previously unpublished texts from his lectures given between 1915 and 1932 and preserved as manuscripts, as well as three texts that have so far only appeared outside of the complete edition.In accordance with Martin Heidegger's instructions to include not only the final versions of the lectures, but expressly also all earlier elaborations and preparatory work, the volume also contains four (previously unpublished) earlier versions of the lecture "On Essence" which is extremely important for the transition to thinking about the history of being or events of Truth", the final version of which Heidegger first published in 1943. Furthermore, a (previously unpublished) "preliminary work" on Plato's "Allegory of the Cave" was recorded. Eight of the total of eighteen texts deal with the question of truth or the nature of truth (and untruth) (in addition to the preparatory work mentioned above, lectures III, XIII and XIV), which is why this topic is a focus of the band. [Publisher's synopsis].