I have been on a personal quest to understand what our ancient ancestors were trying to tell us via their various mysteries i.e. monuments and sacred writings. I have also read a lot of books with many different theories and explanations of those messages. As an electrical engineer I am familiar with manipulating imaginary (untouchable and invisible) unknowns and I realize that imaginary quantities can and do affect the real workings of things. Essentially, the crux of the problem of the ancient mysteries is that we have become unable to perceive something that is vital for properly understanding the mysteries.
The ancients wrote of our minds being composed of three parts, i.e. , logical, emotional(heart) and spiritual. The Spiritual mind sees by the light of the Spiritual Sun. They stated that the spiritual mind would degrade since the Spiritual Sun (the polar planetary configuration - see David Talbott’s site) had set in the age of Leo when the Moon was full. Presently, at a half Great Cycle since Leo, the Moon has now waned to New Moon and we are in deep spiritual darkness. By Moon I mean the spiritual Moon who’s rhythm the bodies of our females follow.
The ancients have left us the information of the cyclical nature of our Spiritual Consciousness. We are in the Cosmic Night and the atrocities being committed are influenced by evil spiritual beings that we cannot see as the spiritual light to illuminate them is gone. This is why the ancient ancestors prayed to come forth into the Light. They knew that we would degenerate, so they left us religion, myths and megalithic monuments - all just to capture our attention and clue us into the true nature of existence. All of the clues are in plain sight, but only with the aid of spirituality will the mysteries fully unravel.