Descartes1March 3, 5961was born in France. His father is a very rich lawyer. When he was 8 years old, his father sent him to a Christian school. He is a very good student. Because of his poor health, the school allows him to study in bed every morning. This habit remained until his later years. His weak body could not stop Descartes from flying in the scientific journey. He entered the University of Poitiers at the age of 65,438+07 and became a lawyer in Paris after graduation at the age of 20. At school, Descartes loved mathematics very much. He happened to meet two priests who loved mathematics in Paris. With the encouragement and guidance of two priests, Descartes spent another 1 year.
Descartes stayed in the French army for several years, but he didn't take part in the battle. He spent a lot of time studying philosophy and mathematics.
From 65438 to 0628, Descartes moved to Holland. He thinks this is a good place for academic research because of social stability and freedom of thought. He lived there for 20 years.
Descartes made many contributions to human society all his life, but the most important contribution was in mathematics. For example, he first used some letters at the beginning to represent constants and some letters near the end to represent variables. The familiar algebra of X and Y comes from Descartes. He also introduced the symbols of exponent and square root.
Descartes was keen on studying mathematics during his service in the army. He thinks whenever he has time. His great discovery was made in bed. One day, he was lying in bed and found flies flying in the air. He stared at the fly and became fascinated. He thinks that the position of the fly at every moment can be determined by three mutually perpendicular planes, which intersect with the position of the fly. On a two-dimensional plane, such as a piece of paper, each point can be determined by two mutually perpendicular straight lines intersecting the point. For example, all points on the earth's surface can be determined by latitude and longitude. Using Cartesian coordinate system, every point on the plane can be represented by an ordered group of two numbers, such as (2,5) or (-3,6). This can be interpreted as "starting point is 2 units east and 5 units north" or "starting point is 3 units west and 6 units south". For points in space, you need to use an ordered group of three numbers, and the third number represents the upper and lower units. An algebraic equation shows how one variable Y depends on the fluctuation of another variable X according to a certain fixed format. For example, y=x2-5, for every value of x, there is a certain value of y, if x is 2, then x is 3; If x is 3, y equals 13, and so on. If the points represented by these X and Y groups [( 1, -3), (2,3), (3, 13), ...] are transformed into points on the plane in Cartesian coordinate system, a smooth curve will be obtained. Each equation represents a special curve.
Descartes combined the two forms of mathematics-shape and number by coordinate method. Analytic geometry makes variables enter mathematics, and immediately makes motion enter mathematics, which lays the foundation for the establishment of calculus.
Descartes wrote this concept in Geometry, one of the methodological appendices published by 1637, which is his only mathematical work.
Descartes wrote many works in his life, most of which expressed his philosophical thoughts. The philosopher's reputation masked Descartes' brilliant achievements in mathematics. Descartes has also made great achievements in other scientific fields: he explained the motion of the sun and planets with the vortex theory of particles and discovered the basic law of light refraction; It is proved that the universe is always in equal motion, and the law of conservation of motion is put forward. The structure and embryonic development of various organs were studied, and the theory of nerve conduction and reflex function was put forward for the first time. He opposed scholasticism, advocated the creation of a philosophy serving practice, and founded deductive method on the basis of summarizing the scientific research methods of the previous generation of scientists. So it should be said that Descartes is a great scholar in the history of modern science and technology.
Unfortunately, in September 1649, Descartes reluctantly succumbed to the invitation of the Swedish court and became a philosophy teacher for Christina, the ruler of Sweden. This eccentric Christina asked Descartes to visit her at 5 am three times a week. On the coldest winter night in Sweden, he goes to the palace three times a week. This is cruel to Descartes, whose lungs are unhealthy. Descartes died of pneumonia before this winter passed (1 1 1 February). His body was shipped back to France except his head. In 2008+0809, a man named Bai got Descartes' skull, which made Descartes finally return to his hometown completely.
In Descartes' life, his achievements were so brilliant. However, he was not conceited about it in his lifetime. On the contrary, he said, "I didn't get any other benefits from studying hard, but I found myself more and more ignorant." These heartfelt words fully show the lofty quality of a great scholar.