Leonardo da Vinci (1452-1519) was born in the middle of the Humanism movement – a search for the lost wisdom of the classical age that broke with the rigid schemes of the Middle Ages. It provided an opening and a new vision of the world: man was no longer subdued and debased by life and by the weight of sin but felt, on the contrary, that he could take the reins and guide his destiny. Humanism brought him to the center of the universe, completely reassessing his position and his potential.

Leonardo was Between Humanism and the Renaissance

This passionate investigation, which began mainly thanks to the studies of Francesco Petrarca (1304 - 1374), also brought the recovery of the hermetic message and with it with the discovery of texts linked to the figure Hermes Trismegistus , the Egyptian Thoth, the ibis - God of wisdom, magic, time measurement, mathematics and geometry, and the inventor of writing. The Latin translation by Marsilio Ficino (1433-1499) of the Corpus Hermeticum , presented to the Medici court in Florence in 1463, spread hermeticism and its religious and occult teachings among scholars; who saw it as a divine revelation reserved for initiates.

Leonardo da Vinci was partly fascinated by secret knowledge and research, but his field was not ancient scrolls and codices, he was an “ omo sanza lettere ” (man without literary culture), he did not know Greek or Latin, but was an assiduous reader of the books of nature and texts in Italian vernacular. Like the humanists, Leonardo wanted to rise to the level of the angels through the study of God's creation.

Possible self-portrait of Leonardo da Vinci. ( Public Domain )

Leonardo's philosophy is presented in his very personal style of notes in books or sometimes in the form of “ pensieri” (thoughts), i.e. stories that include and conclude with a clear and defined moral that often refers to Plato and Aristotle. However, Da Vinci eschews and does not submit to the fashion of auctoritas (the conception that the statements made by the Scriptures or by an erudite author of clear fame cannot be questioned but accepted for the mere fact of being a revelation of a higher knowledge from a secure and accredited source).

On the contrary, he argues vehemently in the face of the concept of sophisma auctoritatis "Ipse dixit ", (he himself said it). For Da Vinci, a thesis cannot be accepted only by virtue of the authority of the person who presents it, but he asserts and supports the superiority of direct experience, " la sapienza é figliuola dell’esperienza ” (wisdom is the child of experience), underlining the influence of Aristotle who taught experience as a methodology of investigation.

Leonardo studied and worked in the era immediately preceding that of Galileo, when science would move away from the supreme principles of Aristotle to establish a method of empirical and scientific investigation that reached the formulation of physical laws. Leonardo was not yet part of it, but he set out on this path through the meticulous study of nature: he cannot be defined as a scientist precisely because his objective is not to go back to physical law through observation and experience, but he nevertheless wished to understand the reasons and motives inherent in nature through reasoning applied to observation, what he called “ cogitatione mentale “ (mental reasoning).

Da Vinci's unique position, with one foot in Humanism and one in the Renaissance, offered him unexpected opportunities: from the humanistic riverbed originated the Renaissance of arts, philosophy, literature - following the establishment of the Seignories and the consequent phenomenon of patronage. The Medici in Florence, the Sforza in Milan, the Estensi in Ferrara, the Montefeltro in Romagna, and others, offered the lands they governed the pax (peace) and tranquility necessary to create courts of intellectuals, writers, artists, and architects, whose thoughts and refined atmosphere helped the Renaissance of art in general. In Rome, an opulent Church , eager to impose its own seal on the city, convened Michelangelo, Bramante, and Raffaello Sanzio, who would leave an eternal mark on the city.

The façade of St Peter’s Basilica with Corinthian columns and inscription. Credit: Ioannis Syrigos

The greatest architects, painters, and sculptors, from Donatello to Brunelleschi, worked in Florence in the Medicis time. It was a period when the great scholars had freedom and decent salaries. In this stimulating environment the Renaissance was generated - a movement of thought and culture that gave birth to a new vision of the world – a place where Leonardo belonged. The discovery of perspective, consequent to this new way of observing the world, helped to renew painting and give new possibilities.

Leonardo da Vinci and the Artistic Anatomy

The humanistic search for truth and an anxiety for knowledge also permeated the artistic environment of the 15th century: in particular, the so-called "Artistic Anatomy", the investigation of the parts of the human body by dissection in order to acquire a better pictorial technique of the limbs, had spread into the studies of the most famous painters. The Artistic Anatomy came mainly from classical Greece, which needed it for its hyper-realistic sculptures and its search for perfection in proportions: the humanistic wave directly resumed this link with the past and assimilated the study of proportions to the search for the maximum aesthetic result.

Leonardo, at only 14 years of age, began to attend the workshop of Andrea del Verrocchio in Florence; serving first as a boy and then as an apprentice. The school of Verrocchio was a real ‘art university’ and exposed the young Leonardo to an infinite number of techniques: probably he found the first rudiments of artistic anatomy here. But it was only later, around 1480, that Da Vinci personally deepened the study of anatomy as a means to increase his ability as an artist. In 1490 he wrote a letter complaining that he could not have human material for his studies.

‘Anatomy of a male nude’ by Leonardo da Vinci. ( Public Domain )

His knowledge increased in later years and oriented his interest to a much deeper level, so that from artistic anatomy he reached real anatomy, particularly from 1507 when he had the opportunity to perform dissections of corpses at the Ospedale di Santa Maria Nuova, in Florence. Three years later, his collaboration with the anatomist Marcantonio Della Torre led to autopsy observations in his Anatomical School in Pavia University between 1508 and 1512, carried out in view of the anatomical work De Figura Humana , which however never saw the light of day due to Della Torre's premature death.

Despite Leonardo's caution and discretion, this type of work and the consequent use of suitable personnel to provide the bodies for the dissections, was noticed. Malicious chatter began to spread about the mysterious occult occupation of master Da Vinci because his work usually took place at night to hide from prying eyes, it was in difficult conditions, and quickly completed because even fresh corpses quickly decayed.

The rumors became insistent and in 1515 Leonardo was accused of necromancy for his anatomical studies on corpses at the Hospital of the Holy Spirit in Rome. The Pope forced him to give up his research.

Anatomy and Physiognomy

Da Vinci's research also extended to Physiognomy, the theory that somatic characters are indications of a person's moral and psychic characteristics. This was not a new idea as it was already present in the Pythagorean school, in the teaching of Aristotle and other philosophers, and in the Renaissance when it was also embraced by Michelangelo.

It is a concept without scientific basis that unfortunately reached the 20th century and was used by Nazi SS doctors to justify racial theories, linking the somatic features of Jews to dangerous characteristics such as greed, selfishness, and serious moral deficiencies. In his time, Leonardo deepened some aspects of it, maintaining however a scientific detachment that would bring him to a more objective vision than the painters of the time: he was convinced that the eye is the mirror of the soul and that some characteristics of the body can be indicative of inner deformities. However, scientific investigation always acted as a discriminating factor for him.

‘Study of five grotesque heads’ by Leonardo Da Vinci. ( Public Domain )

To this end, too, he deepened his studies of grotesque heads, fantastic animals, and even caricature; with the aim of capturing the inner nature of a living being. Although he acknowledged that the human soul can be expressed in facial expressions or in certain characteristics, in the ‘ Treatise on Painting’ he came to the conclusion that: “ Della fallace fisonomia e chiromanzia non mi estenderò, perché in esse non è verità; e questo si manifesta perché tali chimere non hanno fondamenti scientifici ” (I will not use the fallacious physiognomy and fortune-telling because in them there is not truth; and this manifests itself because such chimeras have no scientific basis).

In this field, too, Da Vinci was an innovator as he was the first artist to scientifically study the "movements of the soul" and to express the psychology of the subject and his personality through painting.

A Deeper Investigation: From Artistic Anatomy to Anatomy - Physiology

The intensity and constancy with which Da Vinci pursued his anatomical investigation is a clear indication of a gradual deepening of his interest: it was no longer a question of understanding the forms hidden by the epidermal surface to apply them to painting or sculpture: now he had to understand the reasons, understand the mechanisms that moved the joints, the role of muscles, tendons, and even more the workings of the cardiovascular system, digestion, intestines, internal organs…

In the margin of his anatomical drawings, Da Vinci inserted brief notes, forerunners of the modern scientific language, in the typical dry, clear, and rigorous style which would later be defined as “Leonardo's prose.” Sometimes the feelings of the Genius emerge - the astonishment for the complexity of the human body, which he called “ maravigliosa macchina ” (marvelous machine). This admiration for such a work of engineering would lead him to change the objectives of his anatomical investigation, directing them towards a much wider horizon than he could have imagined at the beginning.

A heart. Leonardo da Vinci wanted to know how the body works. ( Public Domain )

His anatomical drawings are actually questions, queries that Leonardo asked himself: How is muscular force applied to bones? How can the skeleton withstand the weight of the whole body? How does the heart work? How does blood spread in the body? These are the questions of a researcher, of a curious man who is eager for knowledge and doesn't find it in books. Therefore had to do the work himself.

In his painting techniques, the first investigations of Leonardo's Artistic Anatomy can be seen in San Girolamo, an unfinished painting in which he demonstrated his full knowledge of the muscles of the shoulders and neck, thanks to dissections and anatomical drawings.

Leonardo Da Vinci, San Girolamo (1480 ca.) (Public Domain ) and in comparison studies of the muscles of shoulder joint and neck. ( Public Domain )

In Search of the Greatest Secretum

Da Vinci's technique, in addition to drawings, sometimes includes notes and glosses on single sheets that should have been organized, collected, and catalogued in a precise order for proper consultation. However, like many other projects, he was not able to complete this task, burdened with the commitments and journeys necessary to fulfill his duties. This is the reason why his anatomical encyclopedia was not published centuries ahead of future university studies.

The publication of De Anatomia, (Fogli A e B) was to take place only in 1898 by Theodor Sabachnikov, who brought together the drawings from the Windsor collection in the work: Leonardo da Vinci's Manuscripts of the Royal Library of Windsor ( Dell'anatomia, fogli A e B ), Turin, Roux, and Viarengo, 1898.

This method of dissection subverts the methods of the time, which presupposed treatises on anatomy with few illustrations and a lot of text. The text was read and commented on by the teacher in the Anatomical Room while the dissector worked materially on the corpse and the various parts were indicated by the doctor with a long wand. Leonardo recognized the great possibility of pictures to illustrate and teach, highlighting details and clarifying concepts.

Da Vinci is also innovative in this field because he often used the technique of exploded drawing. Once the dissection was completed (from the Latin dissect, dis = separation, secare = cut), that is the cut of the limb or of the internal organ, he recomposed it through exploded drawing: this technique highlights not only Leonardo's questions concerning anatomy, but above all those concerning the reasons why the human body is made in this way and works with these organs.

Leonardo and the Anatomy of the Soul

Over time Leonardo's questions became more important and pressing; particularly when he began to study the reproductive apparatuses of men and women and finally arrived at Pathological Anatomy when he approached disturbing questions about changes in the human body due to age, and performed real autopsies in search of the causes of death. And from these he reached the SECRETUM, the biggest questions on death, on life, on the origin of it, with drawings of the human fetus already formed in the vicinity of childbirth.

Studies of the fetus in the womb by Da Vinci. ( Public Domain )

What is the spark of life? Where does the soul have its seat? These are recurrent questions in Leonardo's investigation and follow lines not far from the thought of the humanist Marsilio Ficino. Soul, mind, and quintessence coincide and are located in the brain.

Renaissance philosophy is uncertain about the physical position of the soul in the human body, recognizing a possible probability to the heart and/or brain: Da Vinci deepened the concept of the “ moti dell’anima ” (soul motions), or emotions, always linked to the heart - but in the course of his dissections he realized that while the heart is an extraordinary machine, it is simply a pump.

During his experiments he learned that the optical nerves carry the images to a specific part of the brain, then following other bundles of nerves he reached the site of impressions and emotions, to finally arrive at the “ ventricolo centrale ” (central ventricle) which he saw as the site of the human soul “ il senso comune " (common sense), and where the memory and personality of the individual is also located.

Ultimately we can say that Leonardo believed, as a transcendent philosopher, in a God-creator, and thought that the painter or artist generally creates in the image of God, being an emanation of Him. He affirmed the idea of the existence of a soul that yearns to return to the Father and all his anatomical investigation can be defined as the Anatomy of the Soul because he wanted to use it to find answers to the most disturbing questions, such as the search for the mystery of the spark of life.

In this sense, the issue of the search for the golden proportion that the Renaissance and Da Vinci studied from Phidias and Fibonacci, should include the so called ‘Signature of God.’ However, Leonardo approached these themes according to his personal vision as an ante litteram scientist, combining metaphysical research with scientific investigation, anticipating Cesare Lombroso's research four centuries later.

Divine Proportions: The Signature of God

In his research Leonardo studied the divine proportion, a geometry inherent in creation that characterizes beauty and harmony. The human body is one of the most evident representations of this and Leonardo highlights it with the Vitruvian Man and by illustrating the De Divina Proportione (1509), a text by the mathematician Luca Pacioli on the golden ratio, a necessarily approximate number that corresponds to 1.618034.

Leonardo Da Vinci, L'Uomo Vitruviano (Vitruvian Man), originally known as Le proporzioni del corpo umano secondo Vitruvio, (The proportions of the human body according to Vitruvius), c. 1490. ( Pixabay License )

Closely linked to the Fibonacci sequence, also known as Phidia’s constant, it is the number that expresses the golden or divine relationship that Greek architects regularly used in their constructions: they were able to divide any line into two segments so that the entire line was about 1.618034 times longer than the longest segment, and the longest segment was about 1.618034 longer than the shortest segment. This proportion was also respected in the statues, where the forearm was in the entire arm to the extent of 1.618034, and so on for all parts of the body and face.

Classical Greece knew that in nature the golden number is continually reappearing; for example in the spirals of growth of sunflower seeds, in the elegant geometries of the Roman cabbage, in the form of a spiral or in other figures such as the lower section of the waves of the sea that form the golden spirals. The Renaissance rediscovered the harmony of the golden number and applied it to painting, identifying the so-called "Signature of God" - the secret of beauty and harmony as a sign of the Creator's hand, as believed by the mathematician Leonardo Fibonacci who had studied it in the 13th century.

Top Image: Leonardo da Vinci portrait and anatomical sketches. Source: klss777 / Adobe Stock

By Pierluigi Tombetti

Pierluigi Tombetti is the author of the recently published ‘ SECRETUM - Il Codice L ’ (SECRETUM – The L Code), researched from the documents concerning Leonardo Da Vinci's trip to Romagna to the service of Cesare Borgia (1502), it is an extraordinary thriller that winds between the present and the past in search of the mysterious SECRETUM. The most interesting and instructive way to get closer to the secret studies of Leonardo and his Anatomy of the Soul. Completely based on accurate historical data.