"Alchemy is an expression of the fact that light is hidden in darkness."
Alchemy is one of those areas of knowledge, like astrology, that has mostly been considered an 'unconventional' idea system. In fact, alchemy was a precursor of modern science and is literally "The Great Work"- ultimately a transformation of one's own mind & state of being.
Like a complex visual & mental puzzle, trying to understand the myriad meanings behind any alchemical works can be an almost absurd task. Even for someone well-versed in art history and symbolism, trying to figure out the story behind the symbols can be mind-boggling.
A while back I got the book Alchemy & Mysticism, The Hermetic Museum that is filled with esoteric art. Although I often browse through the strange imagery with a basic idea of what is behind some of it, it's still a very obscure system of thinking.
I saw this article on Reality Sandwich and it has several excellent observations:
"Contemplating an indescribable divine mystery, according to Jung, "the alchemists did not really know what they were writing about," certainly not with their conceptual mind. Not knowing what they were trying to articulate, the unconscious itself was simultaneously living through the alchemists as it revealed itself to them.
This explains the alchemists' oftentimes confusing, contradictory, and inscrutable description of their art.
Another excellent article, also from Reality Sandwich, discusses the alchemical musings of the late, great neo-shaman... Terence Mckenna: