The political engagement of scientists is not necessarily left-wing, and even when it is, it can take widely varying forms. This is illustrated by the specific character of Dutch scientific activism in the 1930s and 40s, which took shape in a society where ‘pillarized’ social divisions were more important than horizontal class structure. This paper examines how, within this context, the Delft physicist Jan Burgers developed a version of scientific politics, built on a philosophy of value-laden science.