The proportioning system for the Villa Rotonda
Italian Renaissance architect Andrea Palladio is considered one of the most famous and maybe the most influential architect ever, in part because he wrote a book of his work (helping control the narrative of his work) and because he did a good job synthesizing precedent which made so many buildings look ‘Palladian’, whether he designed them or not.
A paper by Raymond Chau and Ruogu Liu explore the use of mathematical concepts in producing the ratios used by Palladio to size rooms and facades and most architectural elements. See their graphics below:
Another paper by Tomas Gracia-Salgado looks at the difference between the proportions Palladio used to build the Villa Rotonda and the proportions he used to describe the building in his book The Four Books of Architecture, published 20 years after the building was completed.