The artist created three versions of "The Bookworm." This one was sold by the artist in New York through his art dealer, HW Schaus, and ultimately was acquired by Milwaukee industrialist, Ren‚ von Schleinitz, who, upon his death, donated the painting to the Milwaukee Public Library. The painting is now on permanent loan to the Grohmann Museum. Spitzweg called it "Librarian." But in public it was called "The Bookworm" in the 19th century. The term is derisive, and was used to describe someone who has eaten his way through books, and is laughed at for being a bookish but unrealistic person. Whether Spitzweg wanted viewers to associate this type of person is unclear for he did not title it "The Bookworm" although he undoubtedly could have.
The painter takes the viewer into a library of the second half of the 18th century, decorated in rococo style. The librarian's dress is also of that age. The old man is standing at the top of the ladder, nearsightedly reading in a book. Another open book is in his right hand. He holds a third one under his left arm, and with his knees the fourth. Here, written works become part of the librarian's physical existence, making him a "bookish" person in the real sense of the word. He is reading in the "Metaphysics" section of a large library. A ray of sunshine is falling through the window on the reading librarian, the open book and the bookshelf: it adds "enlightenment" to ancient metaphysics, the science that researched general world principles, and creates a new metaphysics that is in search of understanding by asking the question "What can I know?" This was the achievement of one of the librarian's contemporaries, philosopher Immanuel Kant (1724 – 1804). But we have reason to doubt that the librarian is "enlightened." His face seems to express a lack of understanding, and his clothes show that he is of prerevolutionary times. His knee breeches, "culottes", were a symbol of "ancien régime" and conservatism ever since the French Revolution. Revolutionaries chose to wear trousers and called themselves "sansculottes," those without knee breeches. The artist painted the lower part of the ladder rather blurred and less clear. We do not know how high it is although it apparently reaches up above the clouds into the sky and has left behind the celestial globe. The librarian may think he has achieved great heights but really he has only climbed a few steps on a library ladder.