Proprietà qualitative e quantitative, intensive ed estensive, e altre distinzioni (I)

Discussing a number of distinctions and definitions by Kant, Hegel, Helmholtz, Duhem, Cohen & Nagel, Bergman & Spence, Hempel, Carnap, Agazzi, and others, we propose a taxonomy of properties employed in different sciences. In the first part we discuss how properties (including relations and meta-properties) are conventionally singled out from basic characters through qualitative, comparative or quantitative concepts. We thus distinguish properties into qualitative and quantitative, and quantitative properties into distributed and undistributed, intensive and extensive. Mental properties do not differ from physical ones in being qualitative rather than quantitative, but qualitative or intensive rather than extensive. On the other hand, objective prediction functions are possible even for qualitative properties. In the second part we distinguish extensive properties into additive, additive up to the whole, and compoundable according to other functions. We thus find that quantities may be limited or unlimited, constitutive or accessory, transferable or non-transferable. Moreover, all properties may be either intrinsic or extrinsic, structural or behavioural, essential or accidental, and these distinctions should not be confused with one another. Finally, our characterization of the intensive-extensive distinction shows it is more neat and objective than granted by Hempel and Carnap