Vincenzo Fano

Abstract: It seems that from an epistemological point of view comparative probability has many advantages with respect to a probability measure. It is more reasonable as an evaluation of degrees of rational beliefs. It allows the formulation of a comparative indifference principle free from well known paradoxes. Moreover it makes it possible to weaken the principal principle, so that it becomes more reasonable. But the logical systems of comparative probability do not admit an adequate probability updating, which on the contrary is possible for a probability measure. Therefore we are faced with a true epistemological dilemma between comparative and quantitative probability.

We present a new thought experiment that raises a threat for Minimal Physicalism, i.e. the thesis according to which mental properties supervene on physical properties. Our proposal is an example of the so called hard problems in philosophy of mind, in particular the problem of maximal consciousness. We do not however presuppose anything about its very nature apart from the minimal, weak assumption that it is determined by first order mental properties. We argue that either Minimal Physicalism is unable to give an adequate account of the new thought experiment we present or has to explain the fact that two numerically distinct but physically indistinguishable individuals have different maximal consciousness due to their spatial location. We contend that this last conclusion is strongly at variance with our contemporary scientific image of the world.