Cladists have pursued, by way of philosophy of science, specific guidelines for ways to make the discipline more “scientific”. For that they incorporated the philosophy of Karl Popper to validate their research program. Kluge, for instance, urged the adoption of standards outlined by philosophers of science, like Hempel, for scientific explanation. In doing that, he used the covering law model of scientific explanation to the philosophy and theory of cladism. While widely known and discussed, this model is severely criticized by philosophers. A number of counter examples were developed, among them the “symmetry thesis”, which has implications in evolutionary biology. Before scrutinize Hempel’s model, I will show how Hennig regarded the issues of explanation and causality in systematics. After, I shall discuss how the cladists did the incorporation of the covering law model. I will argue its criticize each of the main claims made by Kluge in relation to the model itself and its applicability to systematics. I conclude that Hempel’s (and Popper’s) model has little to offer in the way of positive guidelines for constructing successful explanations in cladistics.

包足主义者通过科学哲学追求了使该学科更加“科学化”的具体指导方针。为此，他们采用了卡尔·波普尔的哲学来验证他们的研究计划。例如，克鲁格（Kluge）敦促采用科学哲学家（如Hempel）概述的标准进行科学解释。在此过程中，他将科学解释的覆盖法模型用于集体主义的哲学和理论。尽管这种模式广为人知和讨论，但遭到哲学家的严厉批评。已开发出许多反例，其中包括“对称论”，这对进化生物学有影响。在仔细研究Hempel模型之前，我将展示Hennig如何看待系统学中的解释和因果关系问题。后，我将讨论团伙成员如何将涵盖法律模型纳入其中。我将批评它批评克鲁格（Kluge）关于模型本身及其在系统学上的适用性的主要主张。我得出的结论是，对于构建成功的克拉克主义解释的积极指导方针，亨佩尔（和波普尔）的模型几乎没有提供。