Svante Nordin, professor of history of science and ideas at Lund University, published a book in 2004 called "Ingemar Hedenius: en filosof och hans tid" ("Ingemar Hedenius: a philosopher and his time"). This gives a picture of Ingemar Hedenius based on a rich collection of letters and other documents. According to the text at the back of the book, Hedenius was "a person with strong musical, artistic and literary interests. He liked to play the flute, including performing in public. [...] harsh both in writing and in speech with enemies and opponents, gentle and sensitive with his friends."