All the texts published by M. Berthelot begin with the warning that the contents are to be kept strictly secret, and often contain a statement that some essential process is omitted in order that the unenlightened student may not be able to perform the experiments successfully, lest the wholesale production of gold should be a means of corrupting the whole human race. Undoubtedly the Arabic chemists did claim to have attained a knowledge of the means of transmuting the baser metals into gold but the histories contain various references which show that these claims were adversely criticised by many contemporary thinkers, and that a great many of the Arabic writers regarded chemistry, as it was then understood, as a mere imposture. More than once it was noted that the philosopher al-Farabi, who fully believed that it was possible to change other metals into gold and wrote a treatise on how it might be done, himself lived and died in great poverty, whilst Ibn Sina, who did not believe in alchemy, enjoyed modest comfort and could have commanded wealth had he been willing to accept it. In the course of the middle ages various treatises by Jabir were translated into Latin, where his name appears as Geber, and exercised a considerable influence in producing a western school of alchemy. Before long many original alchemical works were produced in Western Europe and a considerable proportion of these were published under the name of Geber but are pure forgeries. As a result the personality of Geber took a semi mythical character and attempts have been made to account for the diverse and contradictory statements about his life and death, and about the country and century in which he lived by supposing that there were several persons who bore the name; but the fact seems to be that he early attained a position of great prominence as a chemical writer, and that later ages fathered on him a number of apocryphal productions. Berthelot considers that the best evidence associates him with Harran in the early part of the second century of the Hijra. CHAPTER V THE MU`TAZILITES When the Aristotelian philosophy was first made known to the Muslim world it was received almost as a revelation supplementing the Qur´an. At that time it was very imperfectly understood and the discrepancies between it and orthodox theology were not perceived. Thus the Qur´an and Aristotle were read together and regarded as supplementing one another in perfect good faith, but inevitably the conclusions, and still more perhaps the methods, of Greek philosophy began to act as a powerful solvent on the traditional beliefs.