The history of ideas is a field of research in history that deals with the expression, preservation, and change of human ideas over time. The history of ideas is a sister-discipline to, or a particular approach within, intellectual history. Work in the history of ideas may involve interdisciplinary research in the history of philosophy, the history of science, or the history of literature. In Sweden, the history of ideas and science (Idé- och lärdomshistoria) has been a distinct university subject since 6 November 1932, when Johan Nordström, a scholar of literature, was appointed professor of the new discipline in a ceremony at Uppsala University (coinciding with that commemorating the 300-year anniversary of the Battle of Lützen). Today, several universities across the world provide courses in this field, usually as part of a graduate programme.