The three passages assigned from the second half of the essay address the ideas of truth, artistic creation, and the relation of art to history. Heidegger has a distinctive view of each of these, and his account of creation can also be seen to offer a perspective on the relation between artistic form and material.
• The happening of truth (HK 677-682). Although Heidegger’s tone here is quite different from Nietzsche’s in “On Truth and Lie,” you will encounter some of the same language. Nietzsche was an important influence on Heidegger, so it is worth thinking about the relation between their views.
• Truth as unconcealedness (HK 677-679). In this introductory section, Heidegger prepares a reader familiar with typical accounts of truth for something quite different.
• Clearing, refusal, and dissembling (HK 679-681—from “Things are …”). One way of approaching the idea of a clearing of unconcealedness is via the idea of understanding; that is, the unconcealed might be regarded as the thinkable. The ideas of refusal and dissembling then provide a comparable approach to the ideas of the limits of understanding and of misunderstanding. Notice the connections that are sketched (on HK 681) between the two oppositions unconcealedness/concealedness and world/earth.
• Beauty and unconcealedness (HK 681-682—to “… occurs as unconceldedness”). Connections between the preceding general philosophical discussion and art are made here not only in the final comment about beauty but also, as will appear later, in the earlier comments on holding and keeping.
• Truth and createdness (HK 682-683). Here Heidegger poses a number of questions that set the stage for the last part of the essay.
• Bringing forth and standing within (HK 683-692). Although Heidegger gives much less space here to preservation than to creation, the former is important in his later discussion of the nature of art.
• Createdness (HK 683-690). Heidegger, since he thinks an account of art works in terms of matter and form is mistaken, cannot adopt Aristotle’s analysis of making or creation; here he offers his alternative.
• Art vs. craft (HK 683-685). The main task here is to think why Heidegger wants to so sharply distinguish art from even handmade craft (though, given his willingness to reinterpret the Greek term techne, you shouldn’t assume he means by “craft” exactly what you do).
• The self-establishing of truth (HK 685-687—from “In the light of the definition …”). Some of the entries on the list of “happenings of truth” on HK 686f are described a little mysteriously. One suggestion is that the third and fourth are references to Judaism and Christianity, respectively; and Heidegger pretty clearly has philosophy in mind in the last. Notice the reason Heidegger gives for leaving science off the list.
• Two “essential determinations” (HK 687-690). Notice that Heidegger explains each of the two aspects of createdness he identifies by distinguishing art from equipment.
• Rift-design (HK 687-688). The term “rift-design” is an attempt by the translator to capture two meanings of the German word “Riss” that Heidegger plays with here. Notice that Heidegger links the idea of “rift-design” both with form (in German, Gestalt) and with the relation (or perhaps “interface”) between World and Earth.
• Factum est (HK 689-690—to “… present in the manner of a work”). Heidegger uses the Latin phrase factum est (roughly, “(this) was made”) to suggest that a work directs our attention to the fact that it is made without directing our attention to the identity of the artist (as N. N. fecit—i.e., “N. N. made (this)”—would).
• Preserving (HK 690-692). As you think how “standing-within” (HK 691) might be more than mere “artistic enjoyment” (HK 692), recall two earlier discussions of related ideas (at HK 655 and 669f).
• Thing and work (HK 692-694). Heidegger can be seen as here taking stock of the whole of the essay up to this point.
• The nature of art (HK 695-700). This is where Heidegger addresses most directly what has been the key question in the people you have read since Kant (though, as he suggests at the beginning of the epilogue and confirms in the addendum, he doesn’t take himself to have provided an answer).
• Art as poetry (HK 695-697). Heidegger spends much of this section explaining what he means by “poetry” in the broad claim with which he begins. But his real interest here is probably what he has to say about language. Although his positive view of the relation of language to art is not in simple opposition to things that we have seen others say (as when Plotinus speaks of non-discursive wisdom, HK 157, or Schopenhauer rejects allegory, HK 480-486), it does reflect a quite different view of the significance of language, one which he tries to capture in the phrase “projective saying” (HK 696).
• Founding (HK 697-698). The ideas of bestowing (HK 697), grounding (HK 698), and beginning (HK 698) are introduced in quick series of paragraphs in which Heidegger comments on creation and originality in relation to tradition.
• Art grounds history (HK 699-700). This amounts to Heidegger’s conclusion but it also comments on, and raises questions concerning, the place of art in history.
• Epilogue (HK 701-703). This suggests that Heidegger had Hegel in mind in the questions about the place of art in history he asked at the end of the third part of the essay.
• Addendum (HK 704-708). Here Heidegger stands back from and comments on some of the things he said in the essay. The usefulness of these comments to you will be limited (but not eliminated) by the fact that his motivation for them derives from other parts of his philosophical work.