Indeed, it is enlightening to approach a structural design through the lenses of such a genius as the Master. It is important to get enough acquaintance with the anatomy of the whole thing. For Michelangelo, the building is not just a building, but like the human body, it lives and breathes; therefore he could look at a structure and see every part of it as having its unique and special function – as nose, eyes, arms, and other parts of the body have their own special purposes for the proper functioning of the whole physique to the full benefit of the man.
While the writers of medieval times would draw their ideas of architectural outline from the human anatomy, most of them do not conceive of the body as a life form. When drawing from the human body any architectural ideas, the assumed perception is that the body is a miniature of the universe with all its parts functioning in perfect harmony.
This perfect synchronization though, according to the prevailing notions of the artists of those days, could not be achieved practically since – according to them – it was only an ideal and therefore could not be possibly realized in actuality. Hence, the use of numbers and measurements – in short, geometrical approach. For example, one can just look at the available models, such as those crafted by Francisco Di Giorgio (ideal church plan p. 39), and Cesariano (the Vitruvian Figure, 1521 p 40).
The said models, as can be observed, are both replicas of the human body. These architectural designs were common in medieval period. Michelangelo’s attitude was somewhat off tangent when compared to his peers. Indeed, he was different and was very free in terms of his individuality, especially as it was applied to his works. Whereas his contemporaries have chosen to settle for the perfections of mathematical figures/measurements, Michelangelo argued for (as attested in his works) the “motions” and the “emotions. For Michelangelo, everything from the observer to the object – including the vast backdrop of the surroundings – are all interconnected, that when an artist sets himself to plan a building, he should consider the presumed interplay between the object (the architectural design of the building), its backdrop (the environment), and the observer. Remember, the structural design for Michelangelo was a dynamic thing which exerts its influence to the observers.