“The divine Plato, (says Proclus in his MS. Scholia on the Cratylus,)
knew that there are three kinds of Sirens; the _celestial_, which is
under the government of Jupiter; _that which produces generation_, and
is under the government of Neptune; and _that which is cathartic_, and
is under the government of Pluto. It is common to all these to incline
all things through an harmonic motion to their ruling Gods. Hence, when
the soul is in the heavens, the Sirens are desirous of uniting it to the
divine life which florishes there. But it is proper that souls living in
generation should sail beyond them, like the Homeric Ulysses, that they
may not be allured by generation, of which the sea is an image. And when
souls are in Hades, the Sirens are desirous of uniting them through
intellectual conceptions to Pluto. So that Plato knew that in the
kingdom of Hades there are Gods, dæmons, and souls, who dance as it were
round Pluto, allured by the Sirens that dwell there.” See more
concerning the Sirens in my translation of Proclus on the Theology of
Plato, Book the 6th.