De metallorum ortu & causis

in a well-mannered and established city ciuitate no one is allowed, not even a cobbler or any of the lowest craftsmen, to practice his art—the subject of which is lowly—unless he has produced some specimen that satisfies all the masters in that art. Much less, indeed, should the freedom be given to anyone to profess himself a physician, because of the dignity of medicine's subject, namely the human body humani corporis. Who, unless he is a brutish man, will place leather or cloth before the human body? I, for one, think no one. Since it is so, let those men who are wise see to which physician they commit themselves, so that they do not value the lowly objects of mechanics more than their own bodies. Since, however, our purpose is to discuss the causes and origin of metals metallorum against the Chemists Chemistas alchemists, we have therefore deemed it worthwhile to first address what they are and how many there are, and then to examine all their causes one by one.