In Greek mythology, the Muses (Ancient Greek , hai moũsai : perhaps from the Proto-Indo-European root *men- "think") are a sisterhood of goddesses or spirits, their number set at nine by Classical times, who embody the arts and inspire the creation process with their graces through remembered and improvised song and stage, writing, traditional music, and dance. They were water nymphs, associated with the springs of Helicon and with Pieris, from which they are sometimes called the Pierides. The Olympian system set Apollo as their leader, Apollon Mousagetēs. Not only are the Muses explicitly used in modern English to refer to an inspiration, as when one cites his/her own artistic muse, but they are also implicit in words and phrases such as "amuse", "museum", "music", and "musing upon".

According to Hesiod's Theogony (seventh century BC), they are the daughters of Zeus, king of the gods, and Mnemosyne, goddess of memory. For Alcman and Mimnermus, they were even more primordial, springing from Uranus and Gaia. Pausanias records a tradition of two generations of Muses; the first being daughters of Uranus and Gaia, the second of Zeus and Mnemosyne. Another, rarer genealogy is that they are daughters of Harmonia (the daughter of Aphrodite and Ares) which contradicts the myth in which they were dancing at the wedding of Harmonia and Cadmus.

Compare the Roman inspiring nymphs of springs, the Camenae, the Völva of Norse Mythology and also the apsarasa in the culture of classical India.

Muses in myth

The Muses judged the contest between Apollo and Marsyas. They also gathered the pieces of the dead body of Orpheus, son of Calliope, and buried them. They blinded Thamyris for his hubris in challenging them to a contest.

Emblems of the Muses

In Renaissance and Neoclassical art, the dissemination of emblem books such as Cesare Ripa's Iconologia (1593 and many further editions) helped standardise the depiction of muses in sculptures or paintings, who could be distinguished by certain props, together with which they became emblems readily identifiable by the viewer, who would immediately recognize the art with which they had become bound.

Calliope (epic poetry) carries a writing tablet; Clio (history) carries a scroll and books; Erato (love poetry) is often seen with a lyre and a crown of roses; Euterpe (music) carries a flute, the aulos; Melpomene (tragedy) is often seen with a tragic mask; Polyhymnia (sacred poetry) is often seen with a pensive expression; Terpsichore (dance) 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 celestial globe.