M. Vitruvius per Iocundum solito castigatior factus cum figuris et tabula ut iam legi et intelligi possit

The arms which are included in those tensions, when they are extended, must emit both strikes equally and together. But if they are not homotonic of equal tension, they will impede the direct mission of the missiles. Likewise, in theaters, bronze vessels which are placed in cells under the steps by mathematical principle, and the differences of sounds which the Greeks call echeia sounding vessels, they compose for musical symphonies or concerts, divided in the circle of the fourth, the fifth, and the octave, so that the voice of the scenic sound, when it strikes in the arrangements, being increased with increment, may reach the ears of the spectators clearer and sweeter. Likewise, no one will be able to make hydraulic machines and other things that are similar to these organs without musical principles. Furthermore, it is necessary to have known the discipline of medicine, because of the inclinations of the sky, which the Greeks call klimata climates, and the airs of places, which are healthy or pestilential, and the use of waters. For without these principles, no healthy habitation can be made. It is necessary that he also have known the laws that are necessary for buildings, regarding the common walls, the circuit of eaves, and sewers and lights. Likewise, conduits of waters and other things that are of this kind should be known to architects: so that they may take precautions before they begin buildings, lest controversies be left to the fathers of families after works are done: and so that by writing laws, prudence may be provided for both the lessor and the contractor. For if the law has been skillfully written, it will be that both may be freed from each other without entrapment. From astrology, however, he knows the east, the west, the south, the north, and the principle of the sky: the equinox, the solstice, the course of the stars: if someone has not had the knowledge of these, he will not be able to know the principle of the horologe at all. Therefore, since this discipline is so decorated and abounding in various and many studies, I do not think that architects can justly profess themselves as such suddenly, unless they have climbed from boyhood through these steps of the disciplines, nourished by the knowledge of many letters and arts, and have arrived at the high temple of architecture. But perhaps it will seem wonderful to unskilled men that nature can learn such a number of doctrines and contain them in memory. But when one observes that all disciplines have a connection and communication of things among themselves, it will be believed that it can be done easily. For encyclical general/comprehensive discipline is composed as one body from these limbs. Therefore, he who is instructed from tender ages in various studies recognizes the same signs in all literature, and the communication of all disciplines: and for that reason, he knows all things more easily. Therefore, regarding ancient architects, Pythius, who nobly architected the temple of Minerva at Priene, says in his commentaries that an architect ought to be able to do more in all arts and doctrines than those who have brought individual things to the highest clarity by their own industries and exercises. That, however, is not possible in reality. For an architect ought not and cannot be a grammarian such as Aristarchus was, but not ungrammatical: nor a musician such as Aristoxenus, but not unmusical: nor a painter such as Apelles, but not unskilled in drawing: nor a sculptor...