Who really was Jabir ibn Hayyan? Known in Europe as Geber, this Islamic scholar of the Middle Ages is considered the father of alchemy and one of the founders or pioneers of pharmacology and modern chemistry. His figure and even his name are shrouded in mist and uncertainty, which fuel his myth. Legend attributes to him the authorship of between 300 and more than 1000 works on philosophy, alchemy and chemistry. However, doubts and controversy arise from the first two (known) biographical references to him, dating from as early as the 10th century.
According to tradition, Abu Musa Jabir Ibn Hayyan Al-Azdi was born in AD 721 in what is now Iran and spent most of his life in the city of Kufa (Iraq). The son of a pharmacist, he is said to have studied first in Yemen, under the tutelage of the sage Harbi Al-Himyari, and later in Kufa, as a student of Imam Jafar Al-Sadiq, where he learned alchemy (chemistry), pharmacy, philosophy, medicine and astronomy. He became the court alchemist and physician during the reign of Caliph Haroun Al-Rashid. He died in Kufa in AD 815 at the venerable age of 94. The rest is a mystery.
An inspiring teacher or just a name?
It seems possible that the Kitab-al-Fihrist, a catalogue made by Ibn Al-Nadim and dated around AD 987 that compiles all the literature written in Arabic at that time, contributed to the myth surrounding Jabir by attributing to him a huge number of writings. On the other hand, another biography written at about the same time, Notes of Abu Sulayman al-Mantiqi al-Sijistani, questions whether Jabir was the author of such a volume of texts and even raises doubts about his actual existence. Today, the most widely held hypothesis is that Jabir could not have written the entire body of work attributed to him, but only a very limited part, both because of the titanic task that would have been required for an individual to compose more than a thousand works, and also because of the obvious and notable stylistic and thematic differences among the texts of the supposed Jabirian works.
Likewise, this hypothesis also suggests that the so-called Jabirian Corpus is in fact the combined work of some of his pupils and followers of the so-called Brethren of Purity—a secret confraternity whose philosophical-religious teachings enjoyed wide influence and acceptance. The existence of a recognised collective to whom the authorship of the texts could be assigned, and among whom Abu Barkr al-Razi (c.865 – c.925) stands out, is the main argument for questioning whether Jabir was the founder and inspiration behind this group or whether it is simply the name chosen to divinise the origin of these teachings and thereby confer on them a higher (almost supernatural) authority.
The experimental method in the Islamic world
Among the most important contributions present in the Arabic writings attributed to Jabir is the importance of practical knowledge acquired through experience and experimentation, i.e. the adoption of the experimental method in the Islamic world, much earlier than in Europe. Also of significance is the study of matter and its classification into animal, vegetable and mineral; the introduction of intrinsic properties of different substances such as warm, moist and dry; and the possibility of artificially reproducing many naturally occurring phenomena and materials.
Even more significant is the knowledge contained in the Latin Geber texts (also known as the Pseudo-Gerber Corpus), which includes the systematic description of numerous chemical processes and reactions, from the synthesis of acids such as nitric and sulphuric to aqua regia, oxides and salts. In addition, it details many techniques of chemistry such as precipitation, crystallisation and distillation, and provides instructions for making the apparatus and equipment necessary to carry them out. It also introduces methods for improving the quality of a multitude of manufactured products such as the production of steel and other metals (and the passivation of their oxidation); the dyeing and waterproofing of cotton and leather; the chemical analysis of pigments and other natural substances; the purification of gold; and the production of pure mercury from cinnabar. This corpus became a point of reference for scientists of the following centuries, as well as for the craftsmen of different trades. These writings describe practical applications such as the use of manganese oxide in the production of glass so as to avoid the greenish hue produced by iron and obtain a translucent material, or the production of flammable vapour by boiling wine. In short, it was an indispensable and unrivalled source of knowledge of experimental chemistry for the alchemists of the West—at least until the appearance of the new treatises of the 16th century, such as De re metallica (On the Nature of Metals, Georg Bauer, 1556).
The reappearance of his work in the Middle Ages in Europe
As if the enigmatic figure of Jabir and the mystery of the authorship of the work were not enough, there are even more doubts about the reappearance of his work towards the end of the Middle Ages in Europe under the name of Geber, as mentioned above. According to the traditional version, during the 15th century, Jabir’s work was revived and disseminated after being rediscovered and translated into Latin. In the process, the author’s name was also translated from the original Jabir to its Latinised version: Geber. However, once again, the hypothesis that currently generates the most consensus is that Geber and Jabir are not the same person; the former was probably a Spanish-Arab monk or alchemist living on the peninsula who, after translating part of the original Jabirian Corpus and being influenced by it, would have written his own works, signing them under the name of Geber, likely to endow them with greater authority.
This assumption is again based on the obvious divergences between the original writings and the medieval ones, since the latter reflect a much higher degree of knowledge of chemical processes and a far more systematic approach to these phenomena, more in line with the understanding of natural phenomena reached in the 15th century than with that prevailing half a millennium earlier.
But regardless of the question of whether Jabir actually existed and wrote the entire body of work or whether the texts under the name of Geber are the translations of that earlier work or those of an anonymous medieval alchemist, what is beyond doubt is the enormous influence that both the original and the Latinised version had on the development of alchemy—and its final transmutation into a modern science: chemistry, first in the Islamic world and then, centuries later, in Europe.
