Philippe de La Hire, French mathematician and astronomer (d. 1719)

In the vibrant intellectual landscape of 17th and 18th century France, one name stands out as a true polymath: Philippe de La Hire. Born in Paris on March 18, 1640, and passing on April 21, 1718, La Hire was an extraordinary figure who effortlessly traversed the worlds of art, science, and architecture. So profound and diverse were his talents that the renowned Bernard le Bovier de Fontenelle famously declared him "an academy unto himself" – a testament to his profound contributions as a French painter, a brilliant mathematician, an astute astronomer, and an accomplished architect.

Early Life and Artistic Foundations

The seeds of Philippe de La Hire's genius were sown in Paris, where he was born into an artistic lineage as the son of Laurent de La Hire, a distinguished artist himself, and Marguerite Coquin. This familial backdrop undoubtedly nurtured his early inclinations towards the arts. In 1660, demonstrating an ambition to refine his craft, La Hire embarked on a four-year sojourn to Venice, the heart of European painting, to immerse himself in artistic study. Upon his return to Paris, his journey took a fascinating turn when he became a devoted disciple of the groundbreaking geometrician Girard Desargues. From Desargues, he mastered the intricate principles of geometrical perspective, a skill that would deeply influence both his artistic and later scientific work. His dedication to painting culminated in his reception as a master painter on August 4, 1670. Interestingly, the artistic output of Philippe de La Hire has, at times, been mistakenly attributed to his son, Jean Nicolas de La Hire, who, though primarily a doctor, also possessed painting talents.

A Pivot to Science: The Parisian Intellectual Hub

While art laid his initial foundation, it was in the realm of science that Philippe de La Hire truly began to flourish, revealing a remarkable aptitude for mathematics. He sought guidance from the influential French Jesuit Honoré Fabri, a theologian, mathematician, physicist, and noted controversialist of his era. Under Fabri's tutelage, La Hire quickly found his place within an elite intellectual circle in Paris – a veritable "who's who" of 17th-century European thought. This esteemed group included giants such as the Italian astronomer Giovanni Domenico Cassini, the polymath Claude François Milliet Dechales, the brilliant Dutch physicist and astronomer Christiaan Huygens and his brother Constantijn, the philosopher and mathematician Gottfried Leibniz, the foundational philosopher René Descartes, and the erudite friar Marin Mersenne. To be part of such a coterie speaks volumes about La Hire's burgeoning scientific intellect and his capacity to engage with the leading minds of his time.

A Pillar of the French Academy of Sciences

Contributions to Astronomy and Cartography

Philippe de La Hire's growing scientific prominence was formally recognized in 1678 when he was inducted into the prestigious French Academy of Sciences. This membership marked a significant turning point, solidifying his role as a leading scientific figure. He became deeply active as an astronomer, meticulously calculating tables detailing the movements of the Sun, Moon, and planets – essential work for navigation and timekeeping in that era. His ingenuity also extended to engineering, as he designed ingenious contrivances to improve the aiming of early aerial telescopes, pushing the boundaries of observational astronomy. Beyond the celestial sphere, La Hire made indispensable contributions to terrestrial mapping. Between 1679 and 1682, he undertook extensive observations and measurements of the French coastline, providing crucial data for cartographers. In 1683, his expertise was pivotal in mapping France more accurately by extending the crucial Paris meridian northward, a monumental undertaking that shaped the understanding of the nation's geography.

Academic Leadership

His academic influence continued to expand. In 1683, La Hire assumed the distinguished chair of mathematics at the Collège Royal, a testament to his profound mathematical prowess. From 1687 onwards, he further imparted his knowledge and vision at the renowned Académie d’architecture, shaping the minds of future builders and designers in France.

Prolific Writings and Diverse Scientific Exploration

Philippe de La Hire was not merely an active researcher and teacher; he was also a remarkably prolific author, penning numerous treatises that advanced the understanding of various scientific fields. His early work on graphical methods (1673) laid groundwork for visual representation in mathematics. He is perhaps best known for his influential treatise on conic sections (1685), a subject where he brilliantly expanded upon the teachings of his former mentor, Girard Desargues, of whom he was undoubtedly the favorite pupil. His fascination with curves led to a treatise on epicycloids (1694), followed by another on roulettes (1702), and finally, one on conchoids (1708). These works cemented his legacy as a leading geometrician. Beyond original research, La Hire also contributed significantly through translation, bringing Manuel Moschopulus's essay on magic squares to a wider audience, and collecting many previously known theorems on the subject, published in 1705. His comprehensive set of astronomical tables, published in 1702, became a vital resource for astronomers and navigators alike. Demonstrating the breadth of his intellect, La Hire's work extended far beyond pure mathematics and astronomy, delving into fields such as descriptive zoology, the intricate study of respiration, and the complexities of physiological optics.

A Lasting Legacy

The intellectual brilliance of Philippe de La Hire resonated through his family as well. Two of his sons distinguished themselves with their own scientific achievements: Gabriel-Philippe de La Hire (1677–1719) became a respected mathematician, and Jean-Nicolas de La Hire (1685–1727) made notable contributions as a botanist. Today, La Hire's indelible mark on science and exploration is permanently etched into the cosmos; Mons La Hire, a prominent mountain on the Moon, proudly bears his name, a celestial monument to a terrestrial giant of the Enlightenment.

Frequently Asked Questions about Philippe de La Hire

Who was Philippe de La Hire?

Philippe de La Hire (1640–1718) was a highly influential French polymath from the late 17th and early 18th centuries, renowned as a painter, mathematician, astronomer, and architect. He was famously described as "an academy unto himself" due to his vast expertise across multiple disciplines.

When and where was Philippe de La Hire born?

He was born in Paris, France, on March 18, 1640.

What were his primary professions and contributions?

La Hire was initially trained as a painter, studying in Venice and becoming a master painter. He later became a prominent mathematician, known for his treatises on conic sections and other geometric curves. As an astronomer, he calculated celestial tables and designed telescope aiming devices. He was also a respected architect and cartographer, instrumental in mapping the French coastline and extending the Paris meridian.

Which notable scientific figures did he associate with?

He was part of an elite intellectual circle that included Giovanni Domenico Cassini, Christiaan Huygens, Gottfried Leibniz, René Descartes, and Marin Mersenne. He was also a disciple of Girard Desargues and mentored by Honoré Fabri.

What academic institutions was he involved with?

Philippe de La Hire was a member of the prestigious French Academy of Sciences from 1678. He held the chair of mathematics at the Collège Royal and taught at the Académie d’architecture.

Is anything named after Philippe de La Hire?

Yes, Mons La Hire, a mountain on the Moon, is named in his honor, commemorating his significant contributions to astronomy and science.