Insatiably Curious, Relentlessly Observant

I recently learned quite a bit about the self-taught polymath and world-renown genius Leonardo da Vinci, in an excellent biography by Walter Isaacson.

In it I discovered that Leonardo was the illegitimate firstborn son of Piero, in a long line of Florentine notaries. He lived with his birth mother and was apprenticed to the artist Verrocchio in Florence. He was a dandy dresser, favoring rose-colored robes. He was a disdaining contemporary of Michaelangelo (“He paints like a sculptor”), a friend of Nicolo Macchiavelli, and spent the better part of his life seeking patronage from provincial rulers to do the things he wanted to do. He earned a reputation for not finishing works, preferring instead to follow his interests, rather than his commissions.

As an artist, da Vinci is famous for his ability to convey lifelike motion with emotion in his subjects, and as the painter of The Last Supper and the Mona Lisa masterpieces. But his insatiable curiosity and keen observations led to many innovative concepts in art, entertainment, nature, science, geometry, architecture, urban design, engineering, hydraulics, and anatomy, to name just several.

How many other artists do you know who dissect cadavers to learn first-hand what muscles control movements in their subjects? He studied the actual mechanisms that transmit emotions into facial expressions. On one sheet of the ever-present notebooks he clipped to his robes is an anatomical sketch of a pair of lips that seem to suggest a just a hint of a mysterious smile, which resurfaced in his most famous portrait.

But what fascinates me about his anatomical studies is his intuitive leap to connect what he observed in natural stream flow with the internal biological workings of the human heart. Informed by his love of hydraulic engineering, fluid dynamics, and his fascination with swirls and eddies, he made a discovery about the aortic valve that was not fully appreciated for centuries. In 1510, he correctly concluded in that eddies in the blood in the widened section of the aorta were responsible for closing the valve it just passed through.

The common view, which was held by most heart specialists for another 450 years, was that the valve was pushed shut from above once enough blood had rushed into the aorta and began to back up. Most other valves work that way, closing when the flow begins to reverse. But in the 1960s, a team of medical researchers at Oxford used dyes and radiography methods to observe blood flows. The experiments showed that the valve required “a fluid dynamic control mechanism which positions the cusps away from the wall of the aorta, so the slightest reversed flow will close the valve.” That mechanism, they realized, was the vortex of swirling blood that Leonardo had discovered in the aorta root.

In 1991, the Carolina Heart Institute showed how closely the Oxford experiments resembled the ones Leonardo had described in his notebooks. And in 2014, another Oxford team was able to study blood flow in a living human, using magnetic resonance techniques, to prove conclusively that Leonardo was right.

Despite his ground-breaking discoveries and insightful futuristic fancies, Leonardo seemed motivated to accumulate knowledge for its own sake, rather than to be recognized as a scholar or to influence history. He largely left his trove of treatises unpublished. Over the years, and even centuries, his discoveries had to be rediscovered by others. Isaacson concludes, “The fact that he didn’t publish served to diminish his impact on the history of science. But it didn’t diminish his genius.”

I highly recommend the book: you’ll be amazed at the scope of da Vinci’s work, and perhaps, like me, inspired to be more curious and observant.?