The Chicago Public Library system announced it will pull several Dr. Seuss books that contain “racist” or “insensitive imagery” from circulation while it assesses its long-term plans for the books.

“It is important to recognize that what society understands to be relevant and/or common knowledge changes over time, and so too does the Library and the needs of the communities it serves,” Chicago Library spokesman Patrick Molloy said in a statement. “Library staff encourage patrons of all ages to engage critically with our materials, but materials that become dated or that foster inaccurate, culturally harmful stereotypes are removed to make space for more current, comprehensive materials.”