Starting with articles by Bock (1973) and Wiley(1975) in this journal, the field of systematic biologyhas a history, reviewed by Helfenbein and DeSalle(2005), of examining its methods in the context of thephilosophyofsciencearticulatedbyKarlR.Popper(e.g.,1959, 1962, 1983). Two main categories of debates haveemerged in this literature. In one, Popper’s philosophyisassumedtoberelevant,anditisusedtopromotesomesystematic methods and criticize others (e.g., Siddalland Kluge 1997; Kluge 2001), which has led to counter-arguments proposing that the criticized methods areequally compatible with Popper’s philosophy (e.g., deQueiroz and Poe 2001, 2003). In a second categoryof debates, the relevance of Popper’s philosophy tosystematics has been questioned (e.g., Rieppel 2003,2005; Vogt 2008) and defended (e.g., Farris 2013, 2014).These debates can provide insights of at least twodifferent kinds. Systematic biologists can gain a betterunderstanding of how their methods and practicesrelate to general ideas about the nature of science,while philosophers can assess how well Popper’s ideasabout the nature of science describe the methods andpractices in a discipline other than the ones (primarilyphysics and astronomy) upon which those ideas werebased.As part of the continuing debates about Popperianphilosophy and phylogenetics, Farris (2013) recentlyargued that Felsenstein (2004) was incorrect in sugges-ting that Popper’s concept of degree of corroboration,