The concept of source criticism has long had a central role in Swedish history curricula. In this essay, the concept is analysed in three contexts. First, a growing epistemological discrepancy is identified over time with regard to the ways in which the aim of history teaching and the use of source criticism is set down in school curricula. The aim of teaching history has changed towards a more post-structuralist approach, while the concept of source criticism is still described from a more empiricist, epistemological stance. In a second context, Swedish history textbooks are found to use the concept of source criticism in an empiricist, epistemological way. In a third context, upper secondary pupils seem to be confused, navigating between two incompatible epistemological views of historical knowledge. The essay ends with a discussion on how to convert the use of source criticism - from the strait jacket it seems to put on pupils historical thinking, to the necessary and helpful tool it should be.