Structuralism and Mathematical Practice in Felix Klein’s Work on Non-Euclidean Geometry

It is well known that Felix Klein took a decisive step in investigating the invari-ants of transformation groups. However, less attention has been given to Klein’s consider-ations on the epistemological implications of his work on geometry. This paper proposes an interpretation of Klein’s view as a form of mathematical structuralism, according to which the study of mathematical structures provides the basis for a better understanding of how mathematical research and practice develop.