Mexicans paint her with two colors. The beneficent dispenser of harvests
and offspring, she nevertheless has a portentous and terrific phase. She
is also the goddess of the night, the dampness, and the cold; she
engenders the miasmatic poisons that rack our bones; she conceals in her
mantle the foe who takes us unawares; she rules those vague shapes which
fright us in the dim light; the causeless sounds of night or its more
oppressive silence are familiar to her; she it is who sends dreams
wherein gods and devils have their sport with man, and slumber, the twin
brother of the grave. In the occult philosophy of the middle ages she
was "Chief over the Night, Darkness, Rest, Death, and the
Waters;"[133-1] in the language of the Algonkins, her name is identical
with the words for night, death, cold, sleep, and water.[133-2]

She is the evil minded woman who thus brings diseases upon men, who at
the outset introduced pain and death in the world--our common mother,
yet the cruel cause of our present woes. Sometimes it is the moon,
sometimes water, of whom this is said: "We are all of us under the power
of evil and sin, _because_ we are children of the Water," says the
Mexican baptismal formula. That Unktahe, spirit of water, is the master
of dreams and witchcraft, is the belief of the Dakotas.[133-3] A female
spirit, wife of the great manito whose heart is the sun, the ancient
Algonkins believed brought death and disease to the race; "it is she
who kills men, otherwise they would never die; she eats their flesh and
knaws[TN-4] their vitals, till they fall away and miserably
perish."[134-1] Who is this woman? In the legend of the Muyscas it is
Chia, the moon, who was also goddess of water and flooded the earth out
of spite.[134-2] Her reputation was notoriously bad. The Brazilian
mother carefully shielded her infant from the lunar rays, believing that
they would produce sickness;[134-3] the hunting tribes of our own
country will not sleep in its light, nor leave their game exposed to its
action. We ourselves have not outgrown such words as lunatic,
moon-struck, and the like. Where did we get these ideas? The
philosophical historian of medicine, Kurt Sprengel, traces them to the
primitive and popular medical theories of ancient Egypt, in accordance
with which all maladies were the effects of the anger of the goddess
Isis, the Moisture, the Moon.[134-4]

We have here the key to many myths. Take that of Centeotl, the Aztec
godd