Contemporary biographies of Galilei emphasize, in several places, that he was a masterful draughtsman. In fact, Galilei studied at the art academy, which is where his friendship with Ludovico Cigoli developed, who later became the official court artist. The book focuses on this formative effect - it tracks Galilei's trust in the epistemological strength of drawings. It also looks at Galilei's activities in the world of art and his reflections on art theory, ending with an appreciation of his fame; after all, he was revered as a rebirth of Michelangelo. For the first time, this publication collects all aspects of the appreciation of Galilei as an artist, contemplating his art not only as another facet of his activities, but as an essential element of his research.