Abstract

In this paper I discuss the nature of a broad class of biomedical theories which I have termed "middle-range theories." I define them and relate the nature of biomedical theorizing to other investigations, such as a recent inquiry by the National Academy of Sciences. I also suggest that some of the knowledge representation tools from artificial intelligence may give us a purchase on this type of biological theorizing, and try to show in a rather preliminary and exploratory manner by using the lac operon model of genetic control, what some of those AI applications, such as frames and semantic nets, might look like in this context. Finally, I suggest some difficulties, such as the non-monotonicity of reasoning, which such tools may generate.