 A related critique of reductionism in genetics is due to Philip Kitcher (1984). It is not that the complexities of any reduction due to many-one relations between molecular and higher level kinds exceed our cognitive capacities. Rather, the reductive, molecular account does not adequately explain because it does not involve the natural kinds that underlie the appropriate causal relations. Principles of classical genetics (e.g., segregation) are explained by cellular processes (e.g., the behavior of chromosomes in meiosis) because the higher level kinds picked out by cytology are causally relevant. Rephrasing these cellular processes in molecular terms leads to an account that mentions various disjunctive combinations of molecular kinds, while failing to exhibit the unified kinds that are the causes of the cellular process. A key aspect of Kitcher’s argument is that an epistemic account of reduction fails for ontological reasons: it does not capture the natural kind structure of chromosomal phenomena studied by classical genetics.