Analog Constraint Theory: A Post-Kantian Account of Biological Purposiveness

This thesis examines biological purposiveness from a philosophical point of view. Its research question is how the concept of natural purpose (Naturzweck), presented by Immanuel Kant in the Critique of the Power of Judgment (1790), can be understood and reformulated in a way that preserves Kant's insight into the reciprocal relation between the parts and the whole of organisms, while also taking into account the knowledge offered by contemporary biology. The thesis's central claim is that biological purposiveness is neither an obsolete metaphysical relic nor merely a heuristic projected by the observer, but a real organizational property of living systems. This claim is developed by means of Analog Constraint Theory (ACT). According to ACT, organisms are nested, hierarchically organized systems of analog constraints, in which the parts and the whole continuously maintain one another, securing the organism's existence through the closure of constraints. The thesis proceeds in eight chapters. It first reconstructs Kant's concept of purposiveness as a principle of reflective judgment and examines how Philippe Huneman brings this concept into contemporary philosophy of biology. The thesis then presents the scientific background of biological self-organization on the basis of the works of Schrödinger, Prigogine, Turing, and Montévil and Mossio, and on this basis develops ACT as a post-Kantian framework. The theory is illustrated through four case studies, after which four central objections are addressed. On the basis of these examinations, the thesis defends a modest realist interpretation of biological purposiveness. The thesis's conclusion is that Kant's insight into the distinctive organization of organisms remains philosophically fruitful when reformulated through the vocabulary of analog, multilevel, and self-maintaining systems of constraints. Understood in this way, purposiveness is not reducible to mechanism and does not require vitalism. Instead, it describes living systems' real, and at least partly measurable, capacity to maintain, repair, and renew their own viable organization. This is connected to ACT's account of vital normativity: living systems are characterized by non-indifference to their own states, a normativity that is neither moral nor categorical, but a property belonging to the organization of the living system itself. An AI-assisted tool has been used in the language editing, style refinement, and consistency checking of the thesis's English text. Full responsibility for the content and argumentation of the thesis, however, rests entirely with the author.