Geber nsIn existographies, Geber (c.721-c.815) (IQ:175|#250) [RGM:630|1,500+] (MAG:8) (GCE:#) (CR:20), aka ‘Jābir ibn Hayyān’, was an Arabian chemist, noted for his "two principles" theory, of sulfur and mercury, which eventually became, via Paracelsus, the ‘three principles’ theory of generalized chemical properties, one of which, sulphur representative of combustion, was a precursor to the formulation of entropy. [1]

Three principles
To further explain the phenomena of combustion and metallic properties, metals (copper, iron, gold, etc.) were said to be formed out of two elements: sulphur, ‘the stone which burns’, which characterized the principle of combustibility, and mercury, which contained the idealized principle of metallic properties.

Three principles

This evolved into the Arabic three principles: sulfur giving flammability or combustion, mercury giving volatility and its opposite, and salt giving solidity.

See main: Entropy formulations
Geber’s sulphur principle combustion theory was modified by Paracelsus in 1524; Paracelsus’ combustion theory was modified by Johann Becher in 1669 to yield the terra pinguis combustion theory; Becher’s combustion theory was modified in 1703 by Georg Stahl to yield the phlogiston theory; Stahl’s combustion theory was modified in 1787 by French chemist Antoine Lavoisier to yield caloric theory; caloric theory was modified by German chemist Rudolf Clausius in 1850 through 1865 to yield entropy theory, later to be known as the second law of thermodynamics.

Quotes | By
The following are noted quotes:

“As long as a word remains unspoken, you are its master; once you utter it, you are its slave.”
— Geber (c.800) (Ѻ)

“Make books your companions; let your bookshelves be your gardens; bask in their beauty, gather their fruit, pluck their roses, take their spices and myrrh.”
— Geber (c.800) (Ѻ)

“In seeking wisdom, the first step is silence, the second listening, the third remembering, the fourth practicing, the fifth – teaching others.”
— Geber (c.800) (Ѻ)

1. Thims, Libb. (2007). Human Chemistry (Volume Two) (§: Heat and affinity, pgs. 426-36). LuLu.

External links
Jābir ibn Hayyān – Wikipedia.

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