Rosen's no-go theorem for regular categories

The famous biologist Robert Rosen argued for an intrinsic difference between biological and artificial life, supporting the claim that `living systems are not mechanisms'. This result, understood as the claim that life-like mechanisms are non-computable, can be phrased as the non-existence of an equivalence between a category of `static'/analytic elements and a category of `variable'/synthetic elements. The property of a system of being synthetic, understood as being the gluing of `variable families' of analytica, must imply that the latter class of objects does not retain sufficient information in order to describe said variability; we contribute to this thesis with an argument rooted in elementary category theory. Seen as such, Rosen's `proof' that no living system can be a mechanism arises from a tension between two contrapuntal needs: on one side, the necessity to consider (synthetically) variable families of systems; on the other, the necessity to describe a syntheticum via an universally chosen analyticum.