The 1943 lectures scour Heraclitus’ fragments for the meaning of φύσις, “the fundamental word” of the thinkers of the first beginning, in an attempt to show that ἀλήθεια as “dis-closing” (Ent-bergung) is its “essential ground” and the “essential beginning” and, thus, “the fundamental feature of being itself” (87, 175). The 1944 lectures move from glosses on logic and the Greek understanding of λόγος as assertion to an attempt to hear the pre-metaphysical sense of λόγος. The originary significance of λόγος, like that of φύσις in the previous lectures, coincides with the originary meaning of ἀλήθεια (371).