Writers similarly disagree also concerning the number of the Muses; for some say that there are three, and others that there are nine, but the number nine has prevailed since it rests upon the authority of the most distinguished men, such as Homer and Hesiod and others like them.
In Renaissance and Neoclassical art, the dissemination of emblem books such as Cesare Ripa's Iconologia (1593 and many further editions) helped standardize the depiction of the Muses in sculpture and painting, so they could be distinguished by certain props. These props, or emblems, became readily identifiable by the viewer, enabling one immediately to recognize the Muse and the art with which she had become associated. Here again, Calliope (epic poetry) carries a writing tablet; Clio (history) carries a scroll and books; Euterpe (song and elegiac poetry) carries a flute, the aulos; Erato (lyric poetry) is often seen with a lyre and a crown of roses; Melpomene (tragedy) is often seen with a tragic mask; Polyhymnia (sacred poetry) is often seen with a pensive expression; Terpsichore (choral dance and song) is often seen dancing and carrying a lyre; Thalia (comedy) is often seen with a comic mask; and Urania (astronomy) carries a pair of compasses and the celestial globe.
Besides Homer and Virgil, other famous works that included an invocation of the Muse are the first of the carmina by Catullus, Ovid's Metamorphoses and Amores, Dante's Inferno (Canto II), Chaucer's Troilus and Criseyde (Book II), Shakespeare's Henry V (Act 1, Prologue), his 38th sonnet, and Milton's Paradise Lost (opening of Book 1).
The Roman scholar Varro (116–27 BC) relates that there are only three Muses: one born from the movement of water, another who makes sound by striking the air, and a third who is embodied only in the human voice. They were called Melete or "Practice", Mneme or "Memory" and Aoide or "Song". Three ancient Muses were also reported in Plutarch's (46–120 AD) Quaestiones Convivales (9.I4.2–4).
Not only are the Muses explicitly used in modern English to refer to an artistic inspiration, as when one cites one's own artistic muse, but they also are implicit in words and phrases such as "amuse", "museum" (Latinised from mouseion—a place where the Muses were worshipped), "music", and "musing upon". In current literature, the influential role that the Muse plays has been extended to the political sphere. Along with a majority of the Greek Gods, five of the Muses (Thalia, Clio, Calliope, Melpomene and Terpsicore) appeared in the Walt Disney animated film Hercules (based on Hercules), where they narrate the film through gospel-inspired song and dance. These versions of the Muses are modeled after African American Gospel Singers. All nine muses appear in the 1980 film Xanadu, with Actress Olivia Newton-John as Terpsicore. All nine Muses appeared in several paintings in the 72-piece art collection of Dante's Inferno by Dino Di Durante, which is printed in books titled Inferno: The Art Collection and available in 33 languages. This said collection was also featured in the medium length film Dante's Hell Animated by Boris Acosta. In New Orleans, Louisiana, there are streets named for all nine Muses, although their names are commonly anglicized in an unusual manner.
Often Muse-worship was associated with the hero-cults of poets: the tombs of Archilochus on Thasos and of Hesiod and Thamyris in Boeotia all played host to festivals in which poetic recitations accompanied sacrifices to the Muses. The Library of Alexandria and its circle of scholars formed around a mousaion (i. e. "museum" or shrine of the Muses) close to the tomb of Alexander the Great. Many Enlightenment figures sought to re-establish a "Cult of the Muses" in the 18th century. A famous Masonic lodge in pre-Revolutionary Paris was called Les Neuf Soeurs ("The Nine Sisters", that is, the Nine Muses); Voltaire, Benjamin Franklin, Danton, and other influential Enlightenment figures attended it. As a side-effect of this movement the word "museum" (originally, "cult place of the Muses") came to refer to a place for the public display of knowledge.