Theories and Their Applications — A Case of Nonmonotonic Reasoning
Gerhard Schurz · 1995
With an application I mean a kind of application situation x described by a complex pre-theoretical predicate A(x). The theory T entails that for situations of kind A(x) a certain theoretical and empirically contentful claim τ(X) is true. For instance, if T is classical particle mechanics, then A(x) may be “x is a planet of a solar system” ; TX then is the differential equation describing a two particle mechanics. The central question of this paper is: what is the logical nature of the loose if-then relation between an application A(x) and the theoretical claim τ(x) ? The paper presents three approaches to this problem: 1. the deductivistic approach (Popper, logical empirists), 2. the structuralistic approach (Sneed–Stegmïler), and 3. the ceteris–paribus approach (Holzkamp). The approaches are discussed at hand at four examples of scientific theories: (i) Newtonian mechanics, (ii) theories of chemical bond, (iii) psychological theories of aggression, and (iv) the psychological theory of cognitive dissonance.