This work arose from C. G. Jung's realization that a significant part of the modern human's issues is anticipated by what the alchemists understood as their art or process. Although they were hardly aware that they were grappling with a psychological phenomenon, some of them may have sensed the religious or philosophical aspect involved. The author attempts to provide an image of the issues surrounding philosophical alchemy by addressing its central problem, namely the union or overcoming of opposites. He succeeds in demonstrating that the alchemical symbolic world is in a vivid relationship with the latest experiences and insights from the psychology of the unconscious. By exploring these symbols, Jung reveals the connection to the processes occurring in the human unconscious, which can manifest in dreams, spontaneously.