Project through projections. Leonardo da Vinci's design process

Alchemists used to call “powder of projection” the secret ingredient to transform metal into gold. Quite in the same way, the projective process is able to translate “an idea from the mind of a single person into a built form”. The word “project” itself testifies this archaic and metaphorical ascendance but, at the same time, reveals its affinity with optical processes lying behind the phenomenon of vision. Long before its geometrical formalization during XVIII century, artists already used the projective process mainly to produce images from a three-dimensional reality as well as their own mind in order to envision and explore the design space. Leonardo da Vinci was one of the first artists to describe the perspective process to obtain an image by drawing on a glass. He enquired both physiology of vision and the mechanisms of image forming, also through a camera obscura, thus the word “projection” had certainly a faceted sense to him. As an architect he generally approached design through plan schemes to primarily define the dimension of human movements. Then he used to verify his first intuition with isometric-like perspectives as well as vertical sections, in order to set general proportions of spaces. Rarely he adopted sections a guide envisioning tool; more frequently he adopted model-looking isometrics, like in multi-level city studies. Anyway some of his sheets testify a working method that had an enormous influence on the artists of his epoch and has practically remained the same for almost five centuries. But like in an unstoppable metamorphosis, those sheets also demonstrate Leonardo’s attitude for the interdisciplinary (almost a ossimoro to him) theorization that often translated in the impossibility to get to a final product. The analysis of some of his architectural sheets, also by digital procedures, offers the opportunity to reconstruct some of the heterogeneous sources of inspiration as well as his design process and results, often contradicting the effective building possibilities of his age