Of course li omini boni wish to know
. Thus Leonardo (1452-1519) reaffirmed the centrality of knowledge and the need for science, art and technique to be profoundly united. It was precisely this perfect interpenetration that enabled Leonardo to overcome Humanism's distrust of geometry and develop a new disposition towards mathematics, whose essential contribution to artistic creativity must be recognised. From a methodological point of view, he can be considered a forerunner of Galileo because of the essential importance he attached to both experience and mathematics; indeed, it cannot be excluded that Galileo, in developing his mathematical-experimental method, was influenced, albeit indirectly, by Leonardo.
Leonardo's areas of study are multidisciplinary. Starting with mechanics, his brilliant intuition of the principle of inertia should be noted. He also intuited the principle of the composition of forces and that of the inclined plane, which he took as the basis for explaining the flight of birds, translating each intuition into an attempt at realisation or technical design. It is the first time in the history of mankind that the technique-science dialectic has been implemented with such awareness: each provides the other with aids, suggestions and reasons for meditation. In the other fields of physics, it will suffice to mention two brilliant achievements: the intuition of the analogy between the phenomenon of light and wave phenomena, and the discovery of the principle of communicating vessels. Leonardo also carried out in-depth studies in the field of applied hydraulics, from water regulation to the reclamation of vast territories and the design of extraordinary defensive works, including the flooding of the Po Valley.
In geology he explained the origin of fossils. In astronomy, he realised that the Earth can be considered as a star, and even set out to prove that it must reflect light in a similar way to the Moon. In anatomy, he described the structure and functioning of the eye, made several exact observations on the circulation of blood, and studied the muscles of the heart by drawing its valves. Leonardo carried out his anatomy studies, including autopsy, with the dual purpose of learning more about the human body and improving his skills as an artist. On the other hand, these very skills enabled him to reproduce the things he observed in drawings with exceptional precision and fidelity. If we cannot separate the technician from the scientist in him, even less can we separate the scientist from the artist. The systematic use of drawing to study natural phenomena allowed Leonardo to represent reality in a very faithful manner, admirably uniting science and art.
As far as his human profile is concerned, many accounts and anecdotes are contained in Giorgio Vasari's Le Vite, which describes him as a man of wit, a joker who enjoyed playing pranks on those who visited him.
He loved animals, whom he wanted to be respected as living, sentient creatures. It is said that when he saw in a market some birds kept in cages to be sold, he bought them all and let them fly, giving them back their freedom. He was a convinced animal activist and vegetarian, anticipating current trends.
Curious beyond all limits, versatile and thirsty for knowledge, he sought out in the most hidden and infamous corners of the city the characters we see masterfully portrayed in his drawings and paintings. Extraordinary is his pictorial art in which even nature appears perfectly reproduced.
He always regretted not knowing Latin. 'Omo sanza lettere', so he calls himself on a page of the Codex Atlanticus. For Leonardo, who aspired to make art a science and science an art, knowledge of the language of the learned would have been a fundamental requirement to attract the consideration of the academic world. He was undoubtedly a prolific writer, although he only composed the Treatise on Painting, but there are many notebooks he left behind. Before their contents were made known, it took some time as he was extremely jealous of them. To keep his notes a complete secret, he wrote backwards, so that his sheets could only be read in a mirror.
From the distance of five centuries, Leonardo looks at us with a stern gaze as he appears in his self-portrait: but his true face refers to other dimensions: those of a friendly and joking man, a non-conformist, an inimitable genius, a contemporary who hated arrogance, convinced, as he wrote, that true intelligence ignores arrogance.
