In all matters but particularly in architecture, that which is signified is the subject of which we may be speaking and that which gives significance is a demonstration on scientific principles. One who professes himself an architect should be well versed in both directions.

Leave a cavity behind the [wall] facings, and on the inside build walls two feet thick, made of red dimension stone or burnt brick or lava in courses, and then bind them to the fronts by means of iron clamps and lead. The beds and builds, all settling equally and bonded at the joints, will not let the work bulge out, nor allow the fall of the face walls which have been tightly fastened together.

Basilicas should be constructed on a site adjoining the forum and in the warmest possible quarter, so that in winter business men may gather in them without being troubled by the weather.

Burn shavings and splinters of pitch pine, and when they turn to charcoal, put them out, and pound them into mortar with size. This will make a pretty black for fresco painting.

I am moreover inclined to be concise when I reflect on the constant occupation of the citizens in public and private affairs, so that in their few leisure moments they may read and understand as much as possible.

There will be natural propriety in using an eastern light for bedrooms and libraries, a western light in winter for baths and winter apartments, and a northern light for picture galleries and other places in which a steady light is needed; for that quarter of the sky grows neither light nor dark with the course of the sun, but remains steady and unshifting all day long.

The [engineer] should be equipped with knowledge of many branches of study and varied kinds of learning, for it is by his judgement that all work done by the other arts is put to test. This knowledge is the child of practice and theory.