De alchimia opuscula complura veterum philosophorum, quorum catalogum sequens pagella indicabit

without knowledge of natures, seek to perfect the works of nature, and the secret of the whole of philosophy, and the best work, which adorns man with morals, enriches him with benefits, aids the poor, and preserves the human body safe, offering it health, just as one can speak of the virtue of that nature. And therefore, all who are diligent about the apex of this art should strive to insist upon studies, and to draw truth from books, and not from erroneous, otherwise putrid ones, nor from fictitious tales. Because this art is not found except through continuous study and the knowledge of the sayings of the philosophers, or through faithful and knowledgeable information. For he who is sluggish in reading books will not be able to be prompt in preparing things. Likewise, he cannot easily become accustomed to practice whose mind refuses to sweat over theoretical studies.