 Fragmentary evidence complicates our understanding of the Presocratics. Most of them wrote at least one “book” (short pieces of prose writing, or, in some cases, poems), but no complete work survives. Instead, we depend on later philosophers, historians, and compilers of collections of ancient wisdom for disconnected quotations (fragments) and reports about their views (testimonia). In some cases, these sources were themselves able to consult the works of the Presocratics directly. In many others, the line is indirect and often depends on the work of Hippias, Aristotle, Theophrastus, Simplicius, and other ancient philosophers who did have direct access. All of the sources for the fragments and testimonia made selective use of the material available to them, in accordance with their own special, and varied, interests in the early thinkers. (For analyses of the doxographic tradition, and the influence of Aristotle and Theophrastus on later sources, see Mansfeld 1999; Runia 2008; Mansfeld and Runia 1997, 2009a, and 2009b; Laks and Most, 2016.) Despite (or perhaps because of) the fragmentary nature of the evidence, new material occasionally comes to light. In 1962 “The Derveni Papyrus,” probably dating from the second part of the fourth century B.C.E., was discovered in Greece (Betegh 2004, Janko 2001, Kotwick 2017). It is primarily concerned with Orphic religion, including a commentary on a poem attributed to Orpheus. Through the work of scholars to reconstruct and interpret it (see Kouremenos, Pássoglou, &amp; Tantsanaglou 2006) it has become clear that the author of the commentary was familiar with the philosophical theories of the time, and the papyrus has proved valuable to the study of early Greek Philosophy (see, for instance Betegh 2014a and 2014b, and Betegh &amp; Piano 2019). Further new Presocratic material was found in a papyrus from Upper Egypt, now in Strasbourg, that contains texts from Empedocles, some already included in DK, but also previously unknown lines which have complicated our understanding of Empedocles’ thought. (See Martin &amp; Primavesi 1999, and Janko 2001, 2005.) Although any account of Presocratic thinkers has to be a reconstruction, we should not be overly pessimistic about the possibility of reaching a historically responsible understanding of them.