Swedish teacher education policies, in line with the evidence discourse, emphasize subject knowledge, and subject didactics have a vast influence in school and teacher education. But what is the difference between general and subject didactics? In subject didactic text books it is suggested that didactic subject knowledge is more or less sufficient for thinking and planning teaching, and/or that everything concerning school is subject didactics. The aim of the article is to problematize the concept of subject didactics and its claims in relation to planning and teaching. Instead it is suggested that subject matter planning and teaching within school education can be understood as general didactics. This will be presented in two ways. First, one theory strongly involving thinking about subject matter for the planning of teaching, is used to illustrate that this actually is general didactic theories of how content can be thought about, treated and handled in the planning of teaching. It is Klafkis theory of didactic analysis. Secondly, scientific articles in mathematics, history and biology, claimed to be representative for subject didactics will be used to demonstrate that what is stressed in them as subject didactics, in fact seem to be traditional general didactic positions. If this reasoning has credibility it should be reason to investigate more profoundly the intersection between general and subject didactics.