The nature of science is notoriously diﬃcult to pin down. Many think of it as a straightforward progression towards truth, but this is overly simplistic. A radical and controversial model proposed by 20th century physicist and philosopher Thomas Kuhn highlights how far from being linear and truth-oriented science might in fact be.
Kuhn suggests that scientists in a given ﬁeld of study work within a ‘disciplinary matrix’ of common beliefs shared as a community. These include the correct use of instruments, key values and even metaphysical principles. The disciplinary matrix stipulates the important problems in a given area and how to go about solving them. The key aspect of Kuhn’s account of science is his description of the transfer of favour by a scientiﬁc community from one disciplinary matrix to another, an example being the move from classical Newtonian to quantum physics in the early 20th century. Such transitions occur during times of ‘revolutionary science’, when anomalies build up to the extent that the current set of core beliefs is perceived to be inadequate. A new set must be found to replace them. The way any new disciplinary matrix is selected from the many options during a revolutionary period is of vital importance and determines whether science can be said to be a linear progression towards the truth. Kuhn thinks this is not the case.
In his original work, Kuhn claimed that we have no objective means of comparing disciplinary matrices and the theories within them, that even experimental evidence is not theory-neutral, since we interpret it based on the theories we hold to be true. The jumps between disciplinary matrices are, he said, just based on the psychological and sociological factors at play within a community rather than on any that are truly truth-seeking. This argument led Kuhn to be accused of attributing the choice of which disciplinary matrix to adopt entirely to ‘mob psychology’, therefore depriving science of its objectivity.
Kuhn countered this criticism by suggesting that some objective values are applied when choosing between disciplinary matrices: those containing accurate, simple, consistent theories with a wide scope are preferred. He still maintained, however, that these values cannot fully determine the decision and that psychological and sociological factors do play a role. Unfortunately, we cannot guarantee that these objective factors—accuracy, simplicity, consistency—will always lead us towards truth. All we can say is that they have guided us to eﬀective theories in the past, therefore we expect them to continue to do so.
Kuhn’s model, while radical, nevertheless has considerable inﬂuence among philosophers of science, promoting the view that there may be no perfect theory or ‘truth’ that we are heading towards. Rather, science is like an evolutionary process with the selection criteria leading to theories that are increasingly ‘useful’, in that they are good at making predictions but which may have no proximity to the truth about the way the world is.