4.3 Rationality and relativism

Relativism comes in many forms but the basic idea is that some or all of the truth and reality exists only for some and not for others depending on their beliefs. If social constructivism is correct then scientific knowledge is relative because it reflects the values and ideology of scientists. If that is right then the alleged rationality of science is threatened because scientific theories cannot be said to be chosen just on the basis of the evidence.

Please now read to the end of chapter 4 of the Ladyman textbook and the Kuhn and McMullin extracts in Curd and Cover, 2. Pay close attention to how Kuhn distances himself from relativism and the view that scientific knowledge is a social construct, and the problems McMullin finds with his paper. (You will find the relevant part of Curd and Cover's commentary (sections 1–5) very helpful if you want to read more.)

Watch this short video introducing Kuhn’s ideas of paradigm and revolution. You might also want to take a look at this video on the debate between Popper and Kuhn and how the debate influenced methodology in the social and natural sciences.

Optional activity: Paradigms and revolutions

Please use the Revolutions forum to discuss how Kuhn’s view of science differs from those you have considered up to now and whether or not the role he seems to allow for social factors in driving scientific theory change gives ground for scepticism about scientific knowledge.

Group activity: Science and values

Please use the Revolutions forum to discuss whether or not Kuhn’s later work and the arguments of McMullin are sufficient to undo the threat to scientific rationality that many philosophers found in The Structure of Scientific Revolutions. How much does Kuhn’s introduction of epistemic values help with the problems of rationality and relativism?