Controversies, i.e., multiple theory confrontations, may have a strong impact on the development of science. By an analysis of the so-called "resonance controversy" in chemistry the view that controversies and their resolution differ considerably from the process of theory succession is defended. It is argued that controversies are symptomatic of foundational problems, produce theory-scattering or domain-splitting, and induce ontological shifts. An explication is given of the role of existence claims and the applicability of Ockham's Razor in the resolution of controversies. The requirement of a realistic interpretation of theories at all times, as defended by some philosophers, is criticised.
Theory change or, more specifically, theory succession, involves intertheoretic criticism with the purpose of demonstrating merits of a new theory above an old one, and to provoke or stimulate the succession in this way. As observed in cases of two competing theories, this criticism is not necessarily restricted to the functionality of both theories involved. Besides features as domain or explanatory power, the claims about the existence of certain entities made in either theory, or in other words, the ontology of either theory, may be part of the criticism too. As such, intertheoretic criticism plays an important role in science, both as a methodological device for theory change as well as an illumination of the nature of the theories involved.
Intertheoretic criticism may have some special characteristics in the case of two competing theories that may differ in some, or maybe all, aspects from cases of multiple theory confrontations or controversies. In this paper, an inquiry will be made into intertheoretic criticism in the case of controversies regarding multiple theory confrontations. By an analysis of the case of the so-called resonance controversy in chemistry, the foundational character of this kind of criticism will be shown, and by illustrating the important role of existence claims in the controversy, it will be argued that the requirement of a realistic interpretation of theories at all times, as defended by a number of philosophers of science, is untenable.