The famous French mathematician Jean d'Alembert gave no thought to the eighteen-year-old looking for him. The boy had sent several letters of recommendation from scientists and politicians, and that was enough to make d'Alembert angry. But he didn't have the stubbornness of **Pierre Simon Laplace** who soon wrote a short treatise on the general principles of mathematics and sent it to the teacher.

Now d'Alembert would have to change his mind. He read young Laplace's work and two days later sent for him, saying: "*I don't usually give credit to recommendations, and you don't need them. You have shown that you are worthy of being known and I will support you*"Laplace had gotten the opportunity he wanted; from then on he would show the scientific world that he was really" worthy of being known. "

## From Beaumont-en-Auge to the Planets

The boy Pierre Simon Laplace soon revealed extraordinary intelligence in Beaumont-en-Auge, the small town of Normandy where he was born in March 1749. So his uncle, Father, took him to complete his studies in a Benedictine abbey. From there Pierre went to a school in Caen, where his interest in mathematics was accentuated. At eighteen, he goes to Paris and, with the help of d'Alembert, soon achieves the position of mathematics teacher at the Military School. Begins to conduct research, especially in astronomy, which impresses the Academy of Sciences.

He studied in depth one of the most current problems then: the disturbance of planetary movements. It was feared at the time that one planet might get too close to another, causing a catastrophe. But on the basis of calculations, Laplace demonstrated in a series of papers presented to the Academy of Sciences that there was no reason for such fears, for the irregularities of the solar system corrected themselves for infinitely long times.

These works, as well as others on similar subjects, made Laplace's name respected. Invited to attend several academies and teach in the best schools, he accepted. But he continued to study: he devoted himself to chemistry, physics and even medicine, without abandoning mathematics and astronomy.

## The ambitious genius

Many of his theories to date are valid. However, frequent discoveries he announced were based on the work of other scientists, and Laplace hid this fact. This in no way belies his genius, confirmed by authentic and quite important discoveries; but it reveals the ambitious character of this man, who used every means to obtain fame and, with her, honors and rank. Laplace used the great and flattered them.

Thus he was able to cross, covered in glory, a tumultuous period of French history. The preface to the successive editions of his works shows that he did anything to achieve the good pleasure of those in power. In a preface of 1796, he dedicates his works to the Council of the Five Hundred; in 1802, he praises the figure of Napoleon - who had suppressed the Council - and is therefore distinguished with various political positions, including that of Interior Minister. But Napoleon falls in 1814, and now Laplace directs his obeisances to the Bourbons, who occupy the throne, and this gives him the title of marquis, conferred by Louis XVIII. But he was also capable of kind gestures, so much so that he helped several poor researchers.

When he died on March 5, 1827, Laplace had achieved his goal: he was famous and had left an important work.

## The Inheritance of Genius

In the "Treatise on Celestial Mechanics," Laplace brought together all that was sparse in the work of various scientists on the consequences of universal gravitation. In other books, he studied the movements of the moon, Jupiter, and Saturn. His hypothesis about the origin of worlds (the "Laplace theory") is famous. He explained the formation of the universe from an initial nebula, rotating about its own axis, from which the planets of the solar system were thrown off. Although this is now considered a naive placement of the problem, it was at the time of piquing interest and raising debate.

In mathematics, he made in-depth studies of probability theory - in the work "Analytical Probability Theory" - and was the first to fully demonstrate d'Alembert's theorem on the roots of algebraic equations. As a physicist, he left studies on refraction, pendulums, capillary effects, barometric measurements, sound velocity, and solid body dilation. And with his colleague Lavoisier, he built a calorimeter (an instrument to measure specific body heat).

Bibliography: Encyclopedic Dictionary Knowing - Cultural April