De Divina Proportione - Geneva Codex

De Divina Proportione

The golden ratio: this term for a mathematical principal has a magic connotation to this day. This principle had – and has – an especially great significance for art, where it is venerated with cult-like status. The equal proportions according to the golden ratio produced beauty, and during the Renaissance, this influential observation, known since antiquity both for science as well as art, was spread in particular by one work: De Divina Proportione by Luca Pacioli.

A Mathematician and Universal Genius

Luca Pacioli (ca. 1445–1514), an Italian Franciscan priest, is known to this day as a pioneering mathematician. He composed inter alia a famous mathematical textbook and is additionally considered to be a pioneer of double-entry bookkeeping. Nonetheless, his magnum opus is probably the standard reference of geometry De Divina Proportione, originating at the end of the 15th century. Pacioli worked closely with Leonardo da Vinci (1452–1519) since both of them were in the service of the Duke Milan in the years 1496–99. The golden ratio also had its genesis in these years.

The Divine Proportion

De Divina Proportione is a text based on the works of Euclid and other famous mathematicians like Fibonacci and Piero Della Francesca. The divine proportion was depicted with the aid of three-dimensional figures: the divine in geometry. Nonetheless, the golden proportion found its expression in the human body above all, which is considered to be the epitome of the divine proportion. This surely inspired Leonardo to undertake his own proportional studies of the human body.

The Unique Genevan Manuscript

Today, this important work survives in three manuscripts: in Milan, Geneva, and Oxford. The manuscript of the De Divina Proportione, which is housed today in the Geneva University Library in Switzerland, probably originated ca. 1497–98 in Milan. As a special feature, it contains 60 illustrations by Leonardo da Vinci. The various polyhedrons were depicted in masterful constructions, which were wonderfully colored and shaded. The geometric figures hang in their respective cartouches with a description of the illustration. Additionally, a wonderful miniature shows the scene of the manuscript being presented to Ludovico il Moro, the Duke of Milan, along with the escutcheon of the same.