The text describes the similarity between human measurements and columns. It discusses using a "module" as a unit to measure parts of the human body, such as dividing the body into seven parts from head to feet. This method allows for understanding proportions and is applicable to both art and construction.
THE SECOND PART
I. PROBLEM.
Since columns have some conformity with humans in measurement and similarly derive their origin, I wish to follow in the same order, that is, I take the least good reasoning of seven parts for the Tuscan style. For strong men, having generally six members more robust and strong, fit for bearing weights.
I describe then in a similar manner, taking one of these seven parts for the head, which they also divide into four parts, one of which is called a module, to measure the smaller parts. Then I draw a perpendicular line from the top of the head A to the base of the feet H, which I divide into seven ordered parts [...]
The Colossuses have some conformity in measure with humans, who draw the origin of their proportions from them frequently; hence if you make for certain purposes something ordinary, I thus take a man sufficient in size of two heads for the length, and those who have ordinarily more robust and large members; children and others who propose to carry weight and axes, hence after defining parts in four with one defect which I call Module, and it serves to measure smaller parts thereafter.