Uwe A. Meixner

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.