Abstract
This paper examines Knud Grue-Sørensen’s discussion of knowledge as a basic concept in an educational context. In particular, I explore his notions of clarity, justifi cation and truth, and their implications for a moderate realist position. In addition, I highlight Grue-Sørensen’s reflections on the inevitable lack of sufficient evidence in educational communication processes, where, despite personal observation and even proof, remaining the ideal, there are many things both teachers and pupils must accept as a given.