Pseudo-Geber

Pseudo-Geber ("false Geber") is the name assigned by modern scholars to an anonymous European alchemist born in the 13th century (sometimes identified with Paul of Taranto) who wrote books on alchemy and metallurgy in Latin under the pen name of "Geber".

"Geber" is the shortened and Latinised form of the name Jābir ibn Hayyān, a 9th-century Islamic alchemist. In Europe for many centuries from the 14th century onward it was assumed that "Geber" was identical with Jabir ibn Hayyan and that the books of "Geber" had been translated from Arabic. Arabic alchemy was held in high esteem by 13th century European alchemists. Pseudo-Geber adopted the name of his illustrious Arabic predecessor to attach more stature to his own work. The practice of adopting the name of an illustrious predecessor is called pseudepigraphy, and it was not uncommon in the medieval era. Similarly, a wide variety of medieval writings were distributed with the illustrious Aristotle as the stated author that were not written by the original authentic Aristotle. In the domain of alchemy and metallurgy in late medieval Europe, Pseudo-Geber's output was highly influential.

The following set of books is called the "Pseudo-Geber Corpus" (or the "Latin Geber Corpus"). The books were published by printing press several times in the first half of the 16th century. They were in circulation in manuscript for roughly 200 years beforehand. The stated author is "Geber" or "Geber Arabis" (Latin for "Geber the Arab"), and it is stated in some copies that the translator is "Rodogerus Hispalensis" (Latin for "Rodger of Seville").

Also:

Being the clearest expression of alchemical theory and laboratory directions available until then—in a field where mysticism, secrecy, and obscurity were the usual rule—Pseudo-Geber's books were widely read and influential among European alchemists. The Summa Perfectionis in particular was one of the most widely read alchemy books in western Europe in the late medieval period. The next three books on the list above are shorter and are, to a substantial degree, condensations of the material in the Summa Perfectionis. The last two books listed, Testamentum Geberi and Alchemia Geberi, are "absolutely spurious, being of a later date [than the other four]", as Marcellin Berthelot put it, and they are usually not included as part of the Pseudo-Geber corpus. Their author is not the same as the others, but it is not certain that the first four have the same author either.

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