I have a pet theory that things like astrology, tarot, the I Ching, Myers Briggs, etc. are valuable (and therefore stick around) not because they have a supernatural or scientific ability to make correct predictions, but because they provide a useful framework for discussing topics. So for example, even if tarot doesn't give you supernatural insight, the discussion it generates with the card reader may allow you to r…
The Shang of early China are a good example. The oracle bone divination was highly systematized. They would ask the ancestors questions written on bones and shells, with the supposed answers forming along the cracks through the writing when subjected to intense heat. This role was fundamental to the king's power and authority -- a common question was whether and how to perform human sacrifices. They were meticulous r…
When all else fails one can always fall back to intuition.