Uwe A. Meixner

Es wird gezeigt, daß sich Parmenides' Argument gegen Veränderung und Vielheit aus den Fragmenten seines Lehrgedichts so rekonstruieren läßt, daß es entweder formal korrekt wird, oder aber seine Prämisse,,Seiendes ist, Nichtseiendes ist nicht" evidentermaßen richtig ist. Beides zugleich ist nicht zu haben. Es wird plausibel gemacht, daß die Rekonstruktionen in Parmenides' Sinn sind. Betrachtet man sein Argument als formal korrekt, so stellt es, wenn wir das Zeugnis der Erfahrung akzeptieren, eine redactio ad absurdum der auch heute noch vielfach vertretenen Position des Aktualismus „Es gibt nur Aktuales" dar. Parmenides freilich faßte es im Gegenteil als reductio ad absurdum der kognitiven Relevanz der Erfahmng auf.

In the first part, the paper describes in detail the classical conception of intentionality which was expounded in its most sophisticated form by Edmund Husserl. This conception is today largely eclipsed in the philosophy of mind by the functionalist and by the representationalist account of intentionality, the former adopted by Daniel Dennett and David Chalmers, the latter by John Searle and Fred Dretske. The very considerable differences between the classical and the modern conceptions are pointed out, and it is argued that the classical conception is more satisfactory than the two modern ones, not only regarding phenomenal adequacy, but also on the grounds of epistemological considerations. In the second part, the paper argues that classical intentionality is not naturalizable, that is, physicalizable. Since classical intentionality exists (in the experiences that display it), the non-naturalizability of classical intentionality implies psychophysical dualism.

The semantical framework is fundamentally intensional: neither possible worlds nor sets as basic entities, but rather, besides individuals, propositions, properties and relations (in intension). Logical truth is defined in terms of logical form (without mentioning this notion) without employing sets of models and the concept of truth in a model. Truth itself is explicitly defined (without recursion); the truth-conditions for the logical constants of the object-language become theorems derivable from the axioms for "to intend"--the basic semantical relation

The paper provides new perspectives for a dualistic conception of mental causation by putting causation that originates in a nonphysical self into an evolutionary perspective. Nonphysical causation of this type - free agency -, together with nonphysical consciousness, is regarded as being not only compatible with physics, but also as having a natural place in nature. It is described how free agency can work, on the basis of the brain, and how it can be compatible with the result of the Libet-experiment. The necessary condition for the existence of free agency is that the physical macro-world is indeterministic to a degree that is relevant for living beings, that is, for their survival and well-being. From an evolutionary point of view, and on the basis of the facts of consciousness, it is more likely than not that this condition is in fact fulfilled.

Uwe Meixners Essay stellt in gedrängter Form die Hauptgedanken seines 1997 publizierten großen systematischen Entwurfes “Ereignis und Substanz” vor, der neben einer Ontologie im engeren Sinn auch eine Bewusstseinstheorie, eine philosophische Gotteslehre und eine Theodizee beinhaltet. Im vorliegenden Beitrag erläutert er seinen Begriff von Substanz, der eng mit seiner Sicht von Kausalität zusammenhängt und vertritt dabei den radikalen Standpunkt, dass Ereigniskausalität auf Agenskausalität, die von transzendenten Substanzen als Realisationssubjekten getragen werde, reduziert werden könne. Dieser monadische Ansatz wird dann zu einem “eingeschränkten metaphysischen Pluralismus” weiterentwickelt, dessen zentrale These darin besteht, dass das Wirklichmachen – in Meixners Worten die “Realitätsmitteilung an die Welt” – bei einer einzigen Zentralsubstanz liege. Eine Idee, die vor allem aus der Perspektive der modernen japanischen und der chinesischen Philosophie auf Interesse gestoßen ist.

I argue (1) that it is not philosophically significant whether causation is linguistically represented by a predicate or by a sentence connective; (2) that there is no philosophically significant distinction between event- and states-of-affairs-causation; (3) that there is indeed a philosophically significant distinction between agent- and event-causation, and that event-causation must be regarded as an analog of agent-causation. Developing this point, I argue that event-causation's being in the image of agent-causation requires, mainly, (a) that the cause is temporally prior to the effect, (b) that the cause necessitates (is sufficient with necessity) for the effect. Causal necessity is explained as a derivative of nomological necessity, and finally, via a definition of the causal sentence connective, the logic of event-causation is shown to be a part of temporal modal logic.

Ontologically minimal truth law semantics are provided for various branches of formal logic (classical propositional logic, S5 modal propositional logic, intuitionistic propositional logic, classical elementary predicate logic, free logic, and elementary arithmetic). For all of them logical validity/truth is defined in an ontologically minimal way, that is, not via truth value assignments or interpretations. Semantical soundness and completeness are proved (in an ontologically minimal way) for a calculus of classical elementary predicate logic