The key is to dissolve the paradox.
Alchemy speaking about the Lapis Phylosophorum (Philosopher's Sone) which can be created by harmonizing the opposing entities.
As a theory, it is the same way, how life is created by that magnetic spark, which appeared by the results of pulsation of these opposing forces. The secret of life is in the reaction which started by affinity and pulse.
It is the Principle of Dualism, which says everything is dual, as light vs. dark, good vs. bad.
Jung speaks about Christian theories, which are giving priority for the light (pro-bono). (God is light and there is no darkness in him.) These theories claim that light is stronger than darkness, and they define darkness as a kind of lack of light. If is that so, why can not exist light without dark?
What if dark is not empty but full of unknown entities? What if dark is the unconscious and light is the conscious? What If that two are not opposing each others but have different values? What if God is righteousness ( angry at sinners) and merciful in the same time?
Jung said about the Alchemical marriage that it is the conjunction of Eros and Logos. Eros is the feminine, the unconscious, the intuition; and Logos is the masculine, the conscious, the logic. Or Dark and Light. This is the pair with different quantities, and the task is to harmonize them. Those numinous qualities are much more deeper than it could be described by words only.
The human nature has the urge for completion and perfection to reach that harmony, however completion and perfection are not possible to exist together. Since perfection requires light only, and completion requires light and dark together, a paradox appears. How is it even possible than?
In the Alchemical theories the only way to bring birth to the lapis philosophorum, or to create that harmony is, if it is born inside the heart and it is beyond and below in the same time.
In the human body as the vessel;
As above, so below.
The work of Mercury
Where Logic cant reach, there comes love above all law.
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