What is the name given to the fifth component in Western alchemy that informs and unites the other four elements?

Answer

Aether or Quintessence

To speak of the five elements in this context requires introducing Aether, also called Spirit or Quintessence, which is considered the perfect, unchanging substance from which the other four derive.

What is the name given to the fifth component in Western alchemy that informs and unites the other four elements?
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