First.

...regarding this undertaking, you would do us a great favor: for I believe there is not one of us who would not take pleasure in it, and not feel an obligation to you for it.

CLAV. It is truly so: and I, in particular, desire it greatly: for through these [lessons] I will learn the path the musician follows in demonstrating his conclusions: and I will see the difference that exists between the demonstrations made by the musician, which I have never seen, and those made by the mathematician and the geometer, having seen these last two put into practice many times.

GIOS. Sir, there is no need for haste in these matters; it is necessary to proceed slowly. And I promise you that it would take more time than you imagine if I were to take on the task of reasoning about the matters of music as one ought: for it would first be necessary to explain some things to those who have not seen or read the matters that converge in a Demonstration: because I would wish to reason with you about this subject with the Demonstration in hand: and, besides this, it would be necessary to explain what a Demonstration is, and of what it is composed, and many other things which would consume much time. And you would need to imagine that you are having more than one conversation, since in music one thing is linked to another, much like rings joined together in a chain.

ADRI. You increase my desire to hear these things from you: wherefore I pray you to take up this undertaking willingly, for it will provide great relief for my ailment. And I swear to you that if I were younger than I am, I would become a student anew, and I would apply myself in such a way to understanding the reason for the things of music that I would not want anyone to ask me anything that I could not satisfy them upon.

FRAN. This would also be truly and exceedingly pleasing to me, so that while I am in Venice, I might acquire something to take with me to Ferrara, and so I urge you, M. Gioseffo, to take on this burden. But I tell you now, Sir: you ought to be content with being the first of our times in matters of practice, which you possess not without some knowledge of theory, having always delighted in practicing with men learned in this profession. And even if you are not entirely colored, at least you are very well dyed. And you should rejoice in this, for these are gifts that are not given to everyone, and you should thank Divine goodness for them.

ADRI. I truly thank it continuously: but this does not extinguish the thirst I have for knowledge, for it is a thing natural Metaph. 1. cap. 1. to everyone, and indeed it grows in me from day to day. Nor do I grieve at being near the years of decrepitude, but I do grieve that I will have to die just when I am beginning to learn. However, may the will of the Lord always be done. Now, the desire I have to know makes me pray to you again, M. Gioseffo, to do what I have proposed to you.

DESI. I have no less thirst for such a thing than our M. Adriano has: for even though I have seen and read many things demonstrated by various authors, I have not yet been fully satisfied.

GIOS. It would require a river of the largest, I will not say in Italy, but the largest in the world, and not a small brook like mine, to want to extinguish these thirsts so ardent. However, I want to say to you: if so many who have written and treated these things before me have not been able to quench this thirst that you have, what am I to hope for? But because I am greatly indebted to M. Adriano, and I owe him as if he were my father, and a certain sense of honesty does not allow me to refuse this burden, I do not wish to desist from seeing if I can satisfy you with all my strength. For even if you do not receive from me everything you desire, you will at least see that my will is ready to serve you. And I pray God that this time I may be both Musician and Physician at once, which will be of great contentment to me to have performed two operations in one blow: that is, to provide the proper food to the intellect of those who listen to me, and to lift the ailment from those who are in need of health. In the name of the Lord, therefore, I wish to take up this task willingly. It is true, however, that I do not wish to bind myself to demonstrate and resolve for you all those difficulties that can occur in music, since if one wished to demonstrate everything, besides the difficulty and the length of time, it would be, if not impossible, at least difficult to gather them all one by one together and demonstrate them in order.

ADRIA. We do not wish to subject you to this law, since we know all too well that this is an impossible thing.

DESI. Begin then from whichever head you like, for when any doubt arises, we will go about proposing it to you: and