Dear 100 Hour Board,
In response to Board Question #31679 - I may be off base here, but I have always thought that the moon reference referred to the yin and yang. (You know, the little circle that is divided in half, one dark side with a white spot and one white side with a dark spot).
The yang is the masculine, positive side who is associated with things such as strong, positive, sun, happy, bright, dry, etc.
The yin is the negative (think batteries here, they are referring to the balance, not as in bad) side who is associated with cool, dark, mysterious, wet, creative, emotional, etc.
So the dark side of the moon (yin) is mysterious...