Best secondary literature on heidegger. Period. Addendum: when asked, heidegger recommended avoiding all the secondary literature on heidegger. I agree . Richardson uses the word "process" as in "heideggers process of thinking" in describing some of heideggers ways. I don't think heidegger uses this word except in a pejorative description of technological thinking. "Process" makes me think of a process plant on the Rhine river. Also, some secondary literature refers to Dasein in one sentence and in the next sentence refers to the Dasein of the previous sentence as "it." Dasein is not an "it." The secondary literature on heidegger tries to be clear on heidegger which is sort of a contradiction because heidegger said "being clear" is the death of philosophy. Most, or probably all, of the secondary literature on heidegger is full of these little mistakes. Heidegger uses language with great care. Contributions to philosophy is a good way to expose oneself to the language heidegger uses. In sum, I would totally avoid the secondary literature on heidegger and dive right in to his ways. For a beginner, basic writings edited by krell is a series of digestible and "clear" works of heidegger to get started.