Hans Dosch

The problem of the Rota Aristotelis deals with the unrolling of two tightly connected concentric circles with different radii. It is to be found in Chapter 24 of the text Mechanica of the Aristotelian corpus (today generally no longer attributed to Aristotle) and has bothered many authors until the modern age. All these scholars agree that the solution given there is not satisfactory. We conclude that Chapter 24 is close to Aristotle, at least, both from a philological and philosophical point of view. The solution of the problem given in the ancient text can very well be transferred into a modern physical phenomenological explanation.

Nach Leibniz sind es die Summe und das Zusammenspiel der, wie er sie nennt, perceptions insensibles (nicht-wahrnehmbare Perzeptionen), die die (wahrnehmbaren) Perzeptionen begründen. Nicht-wahrnehmbare Perzeptionen bilden für ihn eine Voraussetzung für bewusste Zustände und sind konstitutiv für menschliche Individuen. Mit Blick auf die gegenwärtige Neurowissenschaft argumentieren wir dafür, dass neuronale Hirnaktivitäten als die physikalischen Analoga im Sinne Leibnizens solcher nicht-wahrnehmbaren Perzeptionen interpretiert werden können. Ergebnisse neurophysiologischer Forschung, denen zufolge bestimmte Hirnaktivitäten bewussten (wiederabrufbaren) Zuständen zeitlich vorausgehen, wären dementsprechend klarerweise zu erwarten. Aus diesen und anderen Gründen halten wir den Leibniz'schen Ansatz für eine nützliche und wertvolle Grundlage, um neurophysiologische Ergebnisse in einem Rahmen diskutieren und beurteilen zu können, der über den rein innerphysiologischen hinausgeht

In this contribution, a scientific interpretation of musical harmony is understood as a description in an adequate frame of symbolic forms (in the sense of Cassirer), rather than as a final explanation. I describe different interpretations of musical harmony from the time of the Pythagoreans until the present times. It is noted that a symbolic interpretation of Helmholtz (in the sense of his theory of signs), which was criticized as incomplete by Ernst Mach, is recognized as adequate by Arnold Schönberg.

Examining relativistic quantum field theory we claim that its description of subnuclear phenomena can be understood most adequately from a semiotic point of view. The paper starts off with a concise and non-technical outline of the firmly based aspects of relativistic quantum field theories. The particular methods, by which these different aspects have to be accessed, can be described as distinct facets of quantum field theory. They differ with respect to the relation between quantum fields and associated particles, and, as we shall argue, should be interpreted as complementary (semiotic) codes. Viewing physical theories as symbolic constructions already came to the fore in the middle of the nineteenth century with the emancipation of the classical theory of the electromagnetic field from mechanics; most notably, as we will point out, with the work of Helmholtz, Hertz, Poincaré, and later on Weyl. Since the epistemological questions posed there are heightened with regard to quantum field theory, we considerably widen their approach and relate it to recent discussions in the philosophy of science, like structural realism and quasi-autonomous domains.