The contribution of ancient Greek science to human civilization

The model of astronomy is Ptolemy's masterpiece of astronomy, in which he followed the astronomical thoughts of Plato, Aristotle and Xibaike, and finally put forward a complete and exquisite "geocentric theory". He first thought that everything on the earth fell to the ground, the earth was motionless, it was the center of the universe, and all celestial bodies were influenced by the earth. He assumes that the moon, mercury, Venus, the sun, Mars, Jupiter and Saturn all orbit the earth at a uniform speed in a completely circular orbit, and the stars orbit the whole universe in the outer layer, but his theory is sometimes inconsistent with the observed data of the actual motion of the planets. In order to make his model effective, he created a complex geometric structure to correct its obvious mistakes, that is, the "current wheel-even wheel" system. He believes that all celestial bodies, including the sun, revolve around the earth, and their orbits are determined by the current wheel and the equal wheel. The combination of these two movements constitutes the actual trajectory of a planet. Only in this way can Ptolemy calculate the position of celestial bodies orbiting the earth more accurately.

In optics, Euclid explored the theory of visual perspective from the perspective of geometric optics around 300 BC, and wrote; A book Ptolemy explored the principle of reflection and refraction of light in AD 150, and wrote: a book

In the aspect of gravity, Archimedes studied the balance principle of beam lever and wrote On the Balance of Plane to study the ups and downs of objects. On the floating body, Galen inherited and summarized the medical and physiological achievements since Hippocrates and Aristotle, and made unique discoveries in the study of human heart and vascular system, brain, nerve, kidney and bladder. He has many works, such as the functions of different parts of the human body. Finally, we should sum up the amazing contributions of ancient Greek scientists to mathematics. From 600 BC to 600 AD, mathematics was formed in the hands of the ancient Greeks as an independent rational science. Mathematics in ancient Greece developed in succession in several academic centers. In each center, there are one or two schools led by famous scholars to carry out mathematical research activities. The earliest mathematician in ancient Greece was Thales of Miletus, who brought empirical mathematics from ancient Egypt to Greece to give lectures and study the nature of similar triangles. Then there was Vadagoras of Samos, who studied under Thales and later moved to southern Italy to establish a religious school. Based on the principle of "everything counts", his school has made in-depth research on lattice theory, polygon number theory, number theory and irrational number of square two. After 480 BC, Athens became the political and cultural center of Greece, and many scholars from the following factions were attracted to Athens, gradually forming sophists. One of the main goals of their research is to use mathematics to understand how the universe works. Turning a circle into a square, a quadratic cube and a cubic angle are three famous drawing problems they studied at that time. Around 400 BC, Plato established a college in Athens and continued to lead mathematical research activities. Eudoxus is the biggest mathematician in this school. He has made outstanding contributions to the theory of proportion, the theory of irrational numbers, the exhaustive method and the deductive proof of mathematics.

In the Hellenistic era, the academic center moved to Alexandria, the capital of Ptolemy dynasty. Ancient Greek mathematics entered the heyday of summarization, arrangement and continuous development. Mathematician Euclid used the axiomatic method to sum up all the mathematical research results of the early ancient Greek school into a deductive system and wrote his famous work "The Elements of Geometry". The book has 13 articles, including 477 mathematical propositions.

The characteristics of ancient Greek mathematics are abstraction and emphasis on rationality. They emphasized that mathematics should study abstract concepts. Of course, the concept itself is an attribute of the real thing. The achievements and characteristics of ancient Greek mathematics have laid an important foundation for the development of modern world mathematics.