  Although Nagel's concept of theoretical reduction marks a common starting point for discussions about the apparent reduction of classical genetics, much of the literature on reduction is aimed at seeking a better understanding of the nature of reduction by seeking to replace Nagel's concept with a more illuminating one. This is true of the anti-reductionists, who seek to clarify why molecular genetics cannot reduce classical genetics, as well as those who have been more sympathetic to reductionism. Hence, there are two levels of discourse in the literature examining the question of whether molecular genetics is reducing classical genetics.  One level concerns what is happening in the science of genetics. The other concerns more abstract issues about the nature of (epistemological) reduction.