ABSTRACT
The measurement problem in quantum mechanics first cropped up during the 1930s during a famous series of debates between Einstein and Bohr concerning the physical adequacy – or ‘completeness’ – of the orthodox (Copenhagen) theory.1 As we have seen, it is a topic central to Hanson’s thinking not only with regard to quantum mechanics but also for its wider bearing on the scope and limits of scientific knowledge, the theory-laden character of observations, and the underdetermination of theory by evidence.2 Thus it is frequently adduced in support of his proto-Kuhnian claim that scientists working within different paradigms must be thought of as observing different things or inhabiting ‘different worlds’.3 What I propose to do now is look in more detail at the arguments surrounding this topic and, especially, at various proposals – from Einstein down – for a realist construal of the quantum data (i.e., the empirical measurement-results) that would offer an alternative to Hanson’s idea of the uncertainty principle as placing an absolute limit on our knowledge of objects and events in the microphysical domain. Having set out his arguments already in chapters 4 and 5, I shall not make any further detailed reference to Hanson’s work but assume that the reader who has come this far will have them clearly in mind. Thus my purpose in the remainder of this book is to raise the question: what becomes of the paradigm-relativist approach to issues in the history and philosophy of science if it derives so much of its suasive force from an interpretation of quantum mechanics that has proved increasingly open to challenge?
