STS’s Symmetry Principle as the Foundation for Epistemic Justice

2026 marks the fiftieth anniversary of David Bloor’s Knowledge and Social Imagery, which made the ‘symmetry principle’ the cornerstone of what was then known as the ‘Sociology of Scientific Knowledge’ (the so-called ‘Edinburgh School’) and was soon adopted by Science and Technology Studies more generally. In its most basic formulation, the principle requires the researcher to use the same categories to explain social phenomena, regardless of whether those phenomena are judged to be good or bad, true or false, etc.

In practice, this means that such normative judgements cannot be invoked in the explanation. Although the principle has been heavily criticized (especially by philosophers), I believe that it may be the most interesting philosophical contribution that the field has made. I shall elaborate on this point, especially in the context of ‘epistemic justice’, a branch of social epistemology, which, despite being popular, lacks any positive foundations.