Kinda tough to try to explain, but as I understand it: some of the most ancient knowledge that was shared among humans was from a mythos developed over the ages by people observing, naming, and fictionalising astrological realities and events. The cosmos was a map, and to understand and share knowledge of the map: allegories/metaphors/symbols were made that were representative of, and analogous to, that which was happening in the heavens. As time cycled the map was built and the mythos forged, all while being added to as time rolled on.

This knowledge seems to be the basis for mystical understanding of self and world outside of self that eventually became the symbolic system of the tarot (about which Mark Passio goes into great detail), and the means of describing or predicting world events from observing the deities in the heavens, although the uninitiated 'understanding' of this over time became 'Gods in the sky say X, so this means they are displeased with you' (likely due to a manipulative and corrupt priest-class monopolising the sacred knowledge), rather than the initiate looking to the already categorised celestial bodies as map that one can interpret to gain knowledge of the present future and understanding the ancient stories as allegory, not literally.