# Who is Pierre Simon Laplace?

June 26, 2021“All the phenomena of nature were born in a few constants. His family lived in the Town of Beaumont-en-Auge, in the province of Calvados, France.

Little is known about Laplace’s early childhood. The dark years that surrounded his childhood and youth were due to his arrogant behavior. Her origins from a poor peasant made her blush and she constantly tried her best to hide it. In short, his life story can be summarized with the sentence that he was not born as a peasant boy and did not die as a self-righteous person. Whatever it was, Laplace felt contempt for being a peasant and having a poor family. All his life he could not rid himself of this feeling and thought. This was his weak point.

Laplace showed his first talent at the village school. This success attracted the warm attention of his wealthy neighbors. The thought comes to mind that seeing his wealthy neighbors may have suppressed the above-mentioned feelings when he was a young child. He is said to have had his first successes in theological debates.

Laplace gave himself to mathematics very early. At that time there was a military school in Beaumont. Laplace attended this school. It is said that Laplace later taught mathematics at this school for a while. Again, according to a rumor, there is an opinion that he has a memory ability much more than his mathematical ability. Therefore, at the age of eighteen, Laplace set off for Paris with letters of recommendation from his wealthy patrons. He knew of his high talent, but in this he showed no swelling or exaggeration. Young Laplace came to Paris in complete confidence to conquer the world of mathematics.

He went straight to d’Alembert’s house in Paris. He sent letters of recommendation. But it was not accepted. D’Alembert was not dealing with people who had no assets other than the suggestions of the great and powerful. Laplace felt everything with commendable insight. He returned home and wrote a letter to d’Alembert on the basic rules of mechanics. Thus, he was successful in the game he played. The letter D’Alembert sent to see him read: “Sir, you see I don’t value letters of recommendation at all. You don’t need such letters of praise. You’ve introduced yourself better. That’s enough. It’s my debt to help you.” A few days later, thanks to d’Alembert, Laplace was appointed as a mathematics teacher at the military school in Paris. It was at this time that Laplace gave his great work, the application of Newton’s general law of gravitation to the solar system. Because the astronomer was a mathematician, he was called the French Newton. He can be regarded as the founder of probability theory. He showed his humility by saying “What we know is not much, but what we do not know is much”. He says that he does not care about mathematics, and that he deals with mathematics not for fame and fame, but to overcome his own desires. He thinks of examining the inventions or lives of geniuses and overcoming obstacles by putting himself in their shoes.

He claims that all of his work belongs to him. This saying is not true. For example, in his masterpiece “Sky Mechanics” he used skillfully to give the impression that I created it for future generations. He did not source what he took from other mathematicians, and he was very cunning about appropriating things that were useful to him and borrowed from outside. He took the necessary analysis information for Celestial Mechanics from Legendre and did not even give his name. Only Newton’s name is mentioned.

Laplace considered the three-body problem mentioned in Lagrange for the solar system. He applied Newton’s law of gravitation to the Solar system. He proved that the motions of the planets are determined by the Sun, and that the distances of the planets from the Sun do not change, except for small periodic changes. For Laplace, who was then twenty-four years old, the date was 1773. Because of this success, he was elected a member of the Paris Academy of Sciences. He was receiving the first honor and award of his life and career. He obtained many of the mathematical results he found for use in astronomy. He worked on number theory for a while and left it a short time later. His work on the theory of probabilities again stemmed from his use of it in astronomy. His work, Celestial Mechanics, was published piecemeal over a period of twenty-six years. The first two volumes (Mécanique céleste) dealing with the motions, shapes, and tides of the planets were published in 1799. Two volumes were published in 1802 and 1805, and a fifth volume was published between 1823 and 1825. However, in these works, parts of mathematics were not explained much and interpretations were avoided. In fact, the expression “Easily seen” was used for mathematical calculations. In fact, this easily seen phrase also had a reverse meaning. Even he himself was trying to solve the parts that he said were easily seen for days. Their readers and students were accustomed to grumbling, knowing they would spend weeks working on this idiom later on.