  One suggestion that seems plausible is that a better way of framing the project of cancer research involves commitment to an “explanatory framework.” For instance, Blassimie, et al. (2013) characterize the search for oncogenes as an “explanatory framework”: “causal patterns, schemata (in the sense of Darden 2002), intuitions, hypotheses, evidential standards and various bits of evidence and data coming from different experimental settings and instrumental devices,” which “establish selective and local criteria of causal relevance that drive the search for, characterization and use of biological mechanisms.” Rather than consisting of sets of laws or general principles, such frameworks help generate strategies in the search for causes, and narrow the field of inquiry. Blassime, et al. argue that “explanatory frameworks allow for changes of scientific perspective on the causal relevance of mechanisms without necessarily fully replacing previous explanatory frameworks” (p. 375). Explanatory frameworks, in other words, can “coexist” or be “gradually displaced,” rather than stand in mutually exclusive relations with one another. As new questions arose, and new information was discovered, this explanatory framework became elaborated; depending upon how permissive or restrictive our characterization of this framework, it need not be viewed as at odds with, for instance, attention to the tissue microenvironment in cancer. This sort of multifaceted approach is perhaps what one ought to expect for such a heterogeneous disease, where causes and effects can be described at very different temporal and spatial scales. Much like other complex, multifactorial diseases, cancer is not a single phenomenon, but a heterogeneous class of disease processes, with few definitive properties or unique causes. This makes not only classification, but also explanation, enormously difficult, as we will see below.