ABSTRACT
This chapter discusses a non-scientific example of underdetermination taken from Putnam. It examines a more plausible scientific example of underdetermination, involving Newtonian and Hamiltonian mechanics. The chapter considers various traditional responses for realists and anti-realists. Relativity on a limited basis might be considered a positive, pragmatic feature of Natural Ontological Attitude. In the case of constants, this relativity, occasioned by circumstances of underdetermination, is called into play. Neither the traditional instrumentalist nor constructive empiricist is troubled by underdetermination. Traditional instrumentalists do not hold the theories of science to be true or false: other pragmatic measures are chosen to evaluate theories which relate to their predictive capability and reliability. The modest relativity introduced by underdetermination is not likely to be a common problem in practice. The continuity of reference between theories itself imposes considerable constraints on the significance of any relativity established.
