In Oratorio dei Filippini there is the monumental Biblioteca Vallicelliana. Filippini refers to the Order founded by St. Filippo Neri in 1565: reading was so important for the Order that they used to read and discuss a sacred text at each meal. St. Filippo loved music and he considered it as the best entertainment for the spirit; for this reason, there is a trapdoor connecting the library to the Oratorio below in order to listen to the music even from here.