Vinci, Leonardo da (1452-1519)

Vinci, Leonardo da (1452-1519)

Italian scientist and artist

A true Renaissance man, Leonardo da Vinci was a painter, inventor, scientist, architect, engineer, mathematician, astronomer, and philosopher. Although centuries after his death he remains known primarily as the artist who painted the "Last Supper" and the "Mona Lisa," Leonardo placed a stronger emphasis on his scientific rather than his artistic endeavors. His investigations into almost every field of known science in his time resulted in plans for everything from airplanes to air conditioning systems. Leonardo was also prolific in the field of mathematics and physics , including squaring the circle and calculating the velocity of a falling object.

Born in Vinci, near Florence, Italy, Leonardo was the illegitimate son of Ser Piero da Vinci, a notary, and a peasant woman. Leonardo's father recognized his genius early and ensured that he received a proper education in reading, writing, and arithmetic at his home. Leonardo never attended a university. Rather, at the age of 15, he was sent to Florence, where he became an apprentice painter under Italian sculptor and painter Andrea del Verrocchio (1436–1488). It was during this apprenticeship that Leonardo became absorbed in science, and his interest in technical and mechanical skills was already leading him to sketch various machines. In 1482, Leonardo entered the service of the Duke of Milan as the court painter and advisor on architecture and military issues. According to one report, after studying Euclid, Leonardo became so interested in geometry that he neglected his duties as court painter.

Leonardo's interest in mathematics soon led him to provide several approaches to squaring the circle (constructing a square with the same area as a given circle) using mechanical methods. In his notebooks, Leonardo described and drew plans for both a telescope and a mechanical calculator. Leonardo also formulated several accurate astronomical theories, including one which stated that Earth rotates around the Sun , and another stating the Moon shines because of the Sun's reflected light. Leonardo postulated that the shadowing image of the full moon that appears cradled between the horns of the crescent moon each month is illuminated by light reflected from the earth, a conclusion that was reached by German Astronomer Johannes Kepler (1571–1630) a century later. Through experimentation, Leonardo concluded that the velocity of a falling object is proportional to the time of its fall, predating Sir Isaac Newton's mathematical theory of force and gravity . Leonardo's greatest contribution to science and physics, however, may have been his belief that much of nature could be explained scientifically through a strict adherence to mathematical laws, a fundamental tenet of the philosophy of physics.

Leonardo was a keen observer of the rocks and fossils of his native Northern Italy. Among his 4,000 pages of unpublished notes (an unfinished encyclopedic work) are references to sedimentation occurring in the Arno riverbed and its flood-plain, and observations of rainwater rushing downhill, carrying fossilized rock with it. Leonardo reasoned that the fossils he observed embedded in the rocks of mountains were not washed uphill, and therefore, the hillsides had once been the site of the sea floor. He furthered this argument with his identification of fossilized corals and oysters, found more than 100 mi (160 km) inland. In the layers of stratified rocks and fossils, Leonardo grasped the concept of geologic time .

The Duke of Milan was defeated by the French Armies in 1499, and the following years were nomadic for Leonardo as he traveled to Mantua and then Venice, where he consulted on architecture and military engineering (Leonardo's notebook included plans for a triple-tier machine gun). Leonardo then returned to Florence briefly and, in 1506, returned to Milan where he worked on various engineering projects. Leonardo spent from 1513 to 1516 in Rome, then moved to France, where King Francis I employed him as a painter, architect, and mechanic. By this time, Leonardo worked little on painting and devoted himself primarily to his scientific studies. Leonardo's thousands of sketches and notes focusing on both practical matters of his day and visions of future scientific accomplishments remain as a testament to Leonardo's prolific genius.