PREFACE

In his classic Lives of the Artists, the Italian painter and architect Giorgio Vasari said of Leonardo da Vinci:

His name became so famous that not only was he esteemed during his lifetime but his reputation endured and became even greater after his death.

Indeed, during the Renaissance Leonardo was renowned as an artist, engineer, and inventor throughout Italy, France, and other European countries. In the centuries after his death, his fame spread around the world, and it continues undiminished to this day.

I have been fascinated by the genius of Leonardo da Vinci for several decades and have spent the last ten years studying his scientific writings in facsimile editions of his famous Notebooks. My first book about him, The Science of Leonardo, published in 2007, is an introduction to his life and personality, his scientific method, and his synthesis of art and science. In this second book I go a step further, presenting an in-depth discussion of the main branches of Leonardo’s scientific work from the perspective of twenty-first-century science—his fluid dynamics, geology, botany, mechanics, science of flight, and anatomy. Most of his astonishing discoveries and achievements in these fields are virtually unknown to the general public.

Leonardo da Vinci was what we would call, in today’s scientific parlance, a systemic thinker. Understanding a phenomenon, for him, meant connecting it with other phenomena through a similarity of patterns. He usually worked on several projects in parallel, and when his understanding advanced in one area he would revise his ideas in related areas accordingly.

Thus, to appreciate the full extent of his genius, one needs to be aware of the evolution of his thinking in several parallel but interconnected disciplines. This has been my approach to absorbing and understanding Leonardo’s scientific thought. Having explored and contributed to the systems view of life that has emerged in science in the last thirty years, and having written several books about it, I found it very natural to analyze and interpret Leonardo’s science from that perspective. Indeed, I believe that the ever-present emphasis on relationships, patterns, qualities, and transformations in his writings, drawings, and paintings—the tell-tale sign of systemic thinking—was what initially attracted me to his work and kept me utterly fascinated for so many years.

What emerged from my explorations of all the branches of Leonardo’s science and of his “demonstrations” (as he called them) in his drawings, paintings, and writings was the realization that, at the most fundamental level, Leonardo always sought to understand the nature of life. His science is a science of living forms, and his art served this persistent quest for life’s inner secrets. In order to paint nature’s living forms, Leonardo felt he needed a scientific understanding of their intrinsic nature and underlying principles; in order to analyze the results of his observations, he needed his artistic ability to depict them. I believe that this intersection of needs is the very essence of his synthesis of science and art.

Leonardo thought of himself not only as an artist and natural philosopher (as scientists were called in his time), but also as an inventor. In his view, an inventor was someone who created an artifact or work of art by assembling various elements into a new configuration that did not appear in nature. This definition comes very close to our modern notion of a designer, which did not exist in the Renaissance. Indeed, I have come to believe that the wide-ranging activities of Leonardo da Vinci, the archetypal Renaissance man, are best examined within the three categories of art, science, and design. In all three dimensions he uses living nature as his mentor and model. In fact, as I delved into the Notebooks, I discovered not only Leonardo the systemic thinker but also, to my great surprise, Leonardo the ecologist and ecodesigner.

The persistent endeavor to put life at the very center of his art, science, and design, and the recognition that all natural phenomena are fundamentally interconnected and interdependent, are important lessons we can learn from Leonardo today. Thus, Leonardo’s synthesis is not only intellectually fascinating but also extremely relevant to our time, as I shall argue in the Coda of this book.

In previous decades, scholars of Leonardo’s Notebooks tended to see them as disorganized and chaotic. My own sense, however, is that in Leonardo’s mind, his science was not disorganized at all. In his manuscripts, we find numerous reminders to himself as to how he would eventually integrate the entire body of his research into a coherent whole. I have tried to follow these clues, arranging the material of this present book in a framework that I feel is consistent with Leonardo’s thought. In fact, several of my chapter titles—“The Movements of Water,” “The Elements of Mechanics,” “The Human Figure”—are the ones Leonardo himself intended to use.

Leonardo’s view of natural phenomena is based partly on traditional Aristotelian and medieval ideas and partly on his independent and meticulous observations of nature. The result is a unique science of living forms and their continual movements, changes, and transformations—a science that is radically different from that of Galileo, Descartes, and Newton.

A fundamental underlying idea is that nature as a whole is alive, and that the patterns and processes in the macrocosm of the Earth are similar to those in the microcosm of the human body. I have divided the contents of Leonardo’s scientific work into these two basic categories: nature’s forms and transformations in the macrocosm and in the microcosm. They constitute Parts I and II of the present book.

In the macrocosm, the main themes of Leonardo’s science are the movements of water and air (chapter 1), the geological forms and transformations of the living Earth (chapter 2), and the botanical diversity and growth patterns of plants (chapter 3). In the microcosm, his main focus was on the human body—its beauty and proportions (chapter 4), the mechanics of its movements (chapter 6), and how it compared to other animal bodies in motion, in particular the flight of birds (chapter 7).

Unlike Descartes, Leonardo did not see the body as a machine, but he clearly recognized that the anatomies of animals and humans involve mechanical functions that can be appreciated only with an understanding of the basic principles of mechanics. Consequently, he reminded himself to “arrange it in such a way that the [chapter] on the elements of mechanics with its practice shall precede the demonstration of the movement and force of man and other animals.” I have followed Leonardo’s advice. My chapter on “The Elements of Mechanics” (chapter 5) precedes that on “The Body in Motion” (chapter 6).

As I have mentioned, Leonardo’s ultimate goal—in his science as well as his art—was to understand the nature of life. This persistent quest culminated in his anatomies of the heart and blood vessels and in the embryological studies he undertook in his old age. Leonardo’s explorations of the mystery of life in the human body (chapter 8) are the final highlight of my analysis of his science.

To follow Leonardo’s meandering mind as he moves swiftly between interrelated phenomena—for example, from patterns of turbulence in water to similar patterns in the flow of air, the flight of birds, and on to the nature of sound and the design of musical instruments—is not easy within the linear constraints of written language. I have tried to facilitate this task by including in my text a network of cross-references, as well as copious references to Leonardo’s manuscripts and to the works of the foremost Leonardo scholars. In addition, I have compiled a short chronology of Leonardo’s life and work (see p. 326), which shows how he was constantly involved in several simultaneous projects.

In this and in my previous book, I discuss more than one hundred scientific discoveries made by Leonardo da Vinci during the fifteenth and sixteenth centuries. In the following pages, I present a timeline of his fifty or so most important discoveries, together with indications of the centuries when they were rediscovered by other scientists. This graphic summary is an impressive reminder of Leonardo’s pioneering genius in so many scientific fields.

Leonardo did not publish any of his discoveries, nor do we have any records of written correspondence with the natural philosophers, mathematicians, engineers, doctors, and other intellectuals with whom he maintained regular contact. Although we can assume that he shared some of his insights and working methods in conversations with this circle, we have no evidence of any direct influence of his scientific achievements on subsequent generations of scientists.

Today, as we are developing a new systemic understanding of life with a strong emphasis on complexity, networks, and patterns of organization, we are witnessing the gradual emergence of a science of qualities that has some striking similarities with Leonardo’s science of living forms. We cannot help but wonder how Western science might have developed had Leonardo’s Notebooks been studied by the founders of the Scientific Revolution in the seventeenth century.

From their correspondence it is evident that Galileo, Newton, and their contemporaries struggled with many of the same problems that Leonardo had recognized and often solved one or two centuries earlier. Moreover, they used similar metaphors and reasoned in similar ways, so they would have understood his Notebooks much better than we do today. If they had been aware of his discoveries, the development of science would doubtless have taken a very different path, and Leonardo da Vinci’s influence on scientific thought might have been as profound as his impact on the history of art.

Fritjof Capra

Berkeley

February 2013