Abstract
A well-rehearsed move among teleological realists in the philosophy of biology is to base the idea of genuinely teleological forms of organic self-reproduction on a type of causality derived from Kant. Teleological realists have long argued for the causal possibility of this form of causality—in which a whole is considered the cause of its parts—as well as formulated a set of teleological criteria of adequacy for it. What is missing, to date, is an account of the mereological principles that govern the envisioned whole-to-part causality. When the latter principles are taken into account, we find that there is no version of whole-to-part causality that is mereologically, causally and teleologically possible all at once, as teleological realism requires