1. Concept
Arcanum (Latin, ‘secret’; plural arcana) is found in various contexts of meaning, firstly denoting secrets of nature, and in alchemy secret or confidential knowledge, especially as an appellation for the Philosopher’s Stone, where “arcane language” (see also Argot) refers to the language of alchemists and “arcane discipline’ to the teachings of alchemy. “Arcane discipline” (Latin disciplina arcani) also denotes crucial …