The Multatuli Museum houses the author's personal library, exactly as it was bought from the estate of Douwes Dekker's widow Mimi. The display cabinet contains about 500 books in several languages, published between the 16th and the 19th century, on a wide range of subjects. It may look rather strange - though not for those acquainted with Multatuli - that the collection contains almost no fiction.

Some fifty books contain annotations as well as traces of Multatuli's reading. Multatuli considered his books as utensils and certainly was not a bibliophile. Most of the marks are fingernail scratches in the margins of the books: this was how Multatuli used to indicate the passages that seemed important or interesting to him. His excitement or irritation must have been considerable from time to time, since his nail sometimes went right through the paper.

From the notes we can also derive that Mimi often read out passages to Multatuli. On occasion it was she who wrote comments, though most of the time we get the opinion of both or of Multatuli himself.

Finally, the library collection also contains books with dedications by friends and admirers, sometimes even by enemies. Thus one will find Mijn leven (= My life), a three volume biography by Mina Kruseman, who ultimately fell out with Multatuli, but had written a dedication to him in the first volume.