16th-century Swiss physician Paracelsus was frustrated with established medical practice and academia and he was sometimes on the lam because of his beliefs. He wrote at length about the idea that items in the natural world carried “signatures” in their appearance that could tell you visually how they could be used medicinally.

Research:

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Waite, Arthur Edward. “Lives of alchemystical philosophers based on materials collected in 1815 : and supplemented by recent researches with a philosophical demonstration of the true principles of the magnum opus, or great work of alchemical re-construction, and some account of the spiritual chemistry.” London. G. Redway. 1888. Accessed online: https://archive.org/details/livesofalchemyst1888wait

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Paracelsus and the Doctrine of Signatures

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