1. Caesar, Supreme Ruler while your divine intelligence and supernormal power were acquiring the mastery of the whole world and Roman citizens were glorying in your triumph and your victory, once all your enemies had been obliterated by your indomitable bravery, and all the peoples you had conquered awaited your command, and the Roman People and Senate, freed from fear, began to be governed by your far-ranging plans and decisions, I did not dare, when you were so occupied with such important matters, to publish my writings on architecture and the ideas I had developed after long reflection, for fear that by interrupting you at an inopportune moment I might incur your displeasure
2. When, in fact, I realized that you have taken in hand not only the everyday lives of all our citizens and the organization of the state, but also the development of public buildings so that not only has the state been enriched, thanks to you, with new provinces, but also the majesty of its power is already being demonstrated by the extraordinary prestige of its public buildings, I thought that I should not let slip the opportunity to publish my writings on this subject, dedicated to you, as soon as possible, particularly since I was initially known to your father for my work in this field and was a devoted admirer of his courage. When, therefore, the heavenly council had consecrated your father in the residences of immortality and had passed his power into your hands, my enduring devotion to his memory was transferred to you and found favour with you. And so, with Marcus Aurelius, Publius Minidius and Gnaius Cornelius, I was put in charge of the supply and repair of ballistae, scorpiones and other types of artillery, and, with them, I received my reward: and it was you who granted it to me first and who continued it on the recommendation of your sister.
3. Therefore, since I was indebted to you for this favour, which was such that I need have no financial anxieties for the rest of my life, began to write this work for you since I noticed that you have built much and continue to do so now, and that for the foreseeable future you will ensure that both public and private buildings will so match the majesty of your achievements that they will be handed down in the memory of future generations. I have put in writing precise recommendations so that by examining them, you yourself may become familiar with the characteristics of buildings already constructed and of those which will be built: for in these books I have laid out all the principles of the discipline.
Marcus Vitruvius Pollio
a.k.a. Ten Books on Architecture
c. 40 BC
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