Abstract
Many philosophers have explored the extensive use of non-universal generalizations in different sciences for inductive and explanatory purposes, analyzing properties such as how widely a generalization holds in space and time. We concentrate on developmental biology to distinguish and characterize two kinds of scientific generalizations—mechanisms and principles—that correspond to different explanatory aims. Our analysis shows why each kind of generalization is sought in a research context, thereby accounting for how the practices of inquiry are structured. It also diagnoses problematic assumptions in prior discussions, such as abstraction always being correlated positively with generalizations of wide scope.
