Introduction to the Divine Art of Chemistry

When, therefore, we cannot call nature false, nor sophistical, therefore neither can we the art, nor the science. Therefore, we shall call alchemy entirely true. But if any false and sophistical things occur, they will necessarily be treated in that art or science so that they may be known and avoided, because the discipline of contraries is the same, and otherwise a perfect doctrine could not be made. Those things, however, which have no truth at all, but only appearance and fantasy, such as the art of artificial precious stones, will not be called arts or sciences at all, unless abusively, because the principles are false; therefore they are not natural, for which reason they are not counted in the series of sciences and arts, nor are they subalternated to them at all. Alchemy, therefore, is primarily and per se about things that are called metals, and their accidents and properties, insofar as they can ingeniously be artificially transformed and perfected, by ministering to nature, so that it may follow nature. And its principle appears to be both kinds of intellect, namely speculative primarily, and practical secondarily. For the part that teaches the method of investigation is speculative; but the part that teaches how ministering is to be done, will necessarily be called practical or operative, as is clearly seen in the science of medicine. By reason of form, it is called natural, because it follows nature entirely, both in substantial form and in accidents. And according to this, it is called an art ministering to nature; therefore it is natural, but not metaphysical, because it is not productive; nor is it about the being of reason, because it is not about intellectual being, but real, just as the science of medicine is. Furthermore, it must be noted that natural philosophy, in the science of minerals, teaches about the cognition of metals, namely how they are according to their substance, and how many they are in number, and from how many principles they are, and from what and what kind they are, and how they are, and where they are, and about their generation, and their mixing with one another, for the generation of metals to be made, and about the cognition of metals according to their properties and passions.