For Kant, the main aim of teleology in nature is to identify or to segregate as a particular class of objects certain types of causal systems, specifically, systems of interdependent parts.With the development of physiology as a distinct science at the beginning of the 18th century, the idea of interdependence or reciprocity of parts in a system was well-established as a fundamental principle for the specification of organisms. Kant combined the ideas of teleology and causal reciprocity in his systems-theoretical foundation (...) of organized beings in nature. In the analysis of such systems teleological thinking, i.e. the focus on end states or outcomes, is prevalent because the outcome of each process is relevant for the perpetuation of the system as a whole. Teleological thinking thus plays a methodological role in Kant’s philosophy of nature. Its status ismerely reflective, in that it neither postulates a separate ontological category for living beings nor does it constrain mechanical explanations. But at the same time, teleology is constitutive for a particular class of objects and their scientific study. In Kants Philosophie der Naturwissenschaften kommt der Teleologie eine wesentliche Rolle in der Identifikation und Ausgliederung einer bestimmten Klasse von kausalen Systemen zu: den Systemen aus wechselseitig voneinander abhängigen Teilen. Die Vorstellung der wechselseitigen Abhängigkeit zwischen den Teilen eines Ganzen entwickelt sich mit der Etablierung der Physiologie als einer besonderen Wissenschaft zu Beginn des 18. Jahrhunderts zu einem grundlegenden Prinzip, das der Spezifizierung von Organismen dient. Kant verbindet diese Vorstellung der Wechselseitigkeit mit der Teleologie in seiner systemtheoretischen Fundierung des Begriffs eines organisierten Wesens der Natur. In der Analyse dieser Systeme spielt die Teleologie im Sinne der Konzipierung eines Prozesses ausgehend von seinem Resultat eine wichtige Rolle, weil die Wirkung eines physiologischen Vorgangs für die Erhaltung des ganzen organischen Systems entscheidend ist. Da das System in seiner Einheit und Ganzheit erst in der teleologischen Beurteilung erkannt wird, kommt dem teleologischen Denken in Kants Philosophie der Naturwissenschaften eine methodologische Funktion zu. Die teleologische Beurteilung hat allerdings einen bloß reflektierenden Status, insofern über sie keine neue ontologische Kategorie für Lebewesen begründet wird und die Reichweite mechanistischer Erklärungen durch sie nicht beschränkt wird. Trotzdem ist die Teleologie konstitutiv für die Erkenntnis einer bestimmten Klasse von Gegenständen und deren wissenschaftliche Untersuchung. (shrink)

The meaning of function statements is not clear. Several authors have come up with different explications. By interviewing biologists I tried to get a picture of how they think about function. Two explications of Feature X of organism S has function F came to the fore: (1) X contributes to F and F contributes to survival/reproduction of S and (2) X does F and that contributes to the evolutionary development of X in S via natural selection. Most biologists also related (...) function to adaptation. Gould and Vrba criticize the ordinary use of adaptation in biology. They propose to use it only in the sense of features developed by natural selection for their current role and to use exaptation for features enhancing fitness, but not developed for this by natural selection. This, however, leaves a terminological gap, because as a consequence only effects of adaptations are functions. Effects of exaptations and effects which are not beneficial, like the production of heart sounds, are placed on the same level. That is not in accordance with the practice of biology. That is why a distinction is made between general, adaptive and exaptive functions: function as a pluralistic concept. (shrink)

Several decades ago, Christopher Boorse formulated an influential statistical theory of normative biological functions but it has often been claimed that his theory suffers from insuperable problems such as an inability to handle cases of epidemic and universal diseases. This paper develops a new statistical theory of normative functions that is capable of dealing with the notorious problem of epidemic and universal diseases. The theory is also more detailed than its predecessors and offers other important advantages over them. It is (...) argued here that statistical theories of biological functions should not be so quickly dismissed. (shrink)