ABSTRACT
We have already seen something of Hanson’s influence on debates in philosophy of science over the past four decades.1 In particular, Patterns of Discovery appears to have provided Thomas Kuhn with some of the leading ideas and philosophical motifs that went into the making of his best-known work The Structure of Scientific Revolutions.2 There are various components of the Kuhnian approach that receive rather little explicit attention in his own work but which Hanson pursues with a clarity and vigour – as well as a taste for extreme or paradoxical statements – that enable him to cast a more searching critical light on Kuhn’s much-vaunted ‘revolution’ in the history and philosophy of science. Among them is the way that a certain (orthodox) interpretation of quantum mechanics links up with a range of philosophical theses that likewise stress the incommensurability of different languages, the underdetermination of theory by evidence, the theory-laden character of observation-statements, and hence the radically holistic character of all scientific knowledge.3 Wittgenstein’s influence is everywhere apparent, as for instance when Hanson remarks that ‘[p]ropositions get their force from the whole language system in which they figure’, and takes this as a decisive argument against any theory of quantum mechanics that would seek to maintain the correspondence-principle (or the continuity between quantum and ‘classical’ languages) in defiance of orthodox quantum-theoretical precept (Hanson, p. 154).4 What he means here by ‘the whole language’ is most definitely not the entire set of propositions that jointly comprise our current understanding of quantum and classical physics but rather the language of quantum theory holistically construed. Thus any such radical paradigm-change as that brought about by the passage from classical to quantum physics – or (by retroductive analogy) from Ptolemaic to Copernican astronomy – will ipso facto entail a process of full-scale contextual redefinition which may in principle extend to the ‘whole language’ of accepted scientific belief.
