Until recently, philosophers have either denied that there is such a thing as philosophy of technology or have held it in contempt. A philosophy of technology would be as absurd as a philosophy of sport, they scoffed. Nowadays philosophers pay more attention to this crucial area We recognize that technology raises economic, moral, and social problems that demand philosophical attentioa But we still tend to overlook that applied science has conceptual problems – problems for the philosopher of science – independent of the moral, social, and aesthetic problems of technology. It is the need for philosophical study of these conceptual problems that I want to stress.

To make clear that these problems are scientific problems separate from the familiar problems of decision theory, costbenefit analysis, and social responsibility, I shall choose two examples at a fairly high level in the application of physics – one quantum, one classical.

Let me begin by briefly explaining the concept of ‘interpretation’ relevant to this discussion.

Certain physical theories postulate abstract structural constraints which events are held to satisfy. Such theories are termed ‘principle theories’. Interpretations of principle theories aim to explain their relation to the theories they replace. Interpretations are therefore concerned with the nature of the transitions between theories.

Theories of space-time structure provide the most accessible illustration of principle theories. For example, Newtonian mechanics in the absence of gravitation represents the 4-dimensional geometry of space-time by the inhomogeneous Galilean group, which acts transitively in the class of free motions, i.e. the inhomogeneous Galilean group is the symmetry group of the free motions: it is a subgroup of the symmetry group of every mechanical system, and the largest such subgroup. Einstein’s special principle of relativity is the hypothesis that the symmetry group of the free motions is the Poincaré group.