Christiaan Huygens, a Dutch philosopher and mathematician, was one of the leading scientists in the 17h century. He started by trying to disprove theories that had been established by Ancient Greeks in geometry. He was interested in telescopes and astronomy, anc spent a lot of time designing methods to improve the mechanical and optic performance of telescopes. In his book entitled "Systema Saturnium' published in 1659, he noted the discovery of the rings around the planet Saturn, and made observations about the planets, the Moon, and Orion Nebula. His keen interest in the field of astronomy led him to measure time and other matters that relate to mechanical physics. One of his most important contributions was that he explained the vital principles of classical physics like centripetal force and gravity in a vacuum in another book of his. Huygens also put forward a theory explaining the wave behaviour of light. His reputation as a scientist and a scholar became known worldwide, and remains so to this day.
Pythagoras was an Ancient Greek mathematician and philosopher who lived more than 500 years before Christ. He spent most of his life in the Greek colonies in Sicily and southern Italy. He was also a philosopher, and founder of the religious movement called Pythagoreanism. Pythagoras had a group of disciples who followed him around, and taught other people what he had taught them. He made crucial contributions to modern philosophy, as well as mathematics, science, and religious mysticism. It is also believed that he had a significant influence on medicine, music, astronomy, and divination. Pythagoras is best known for the mathematical theory named after him. He is without doubt, one of the greatest scientists not only of the ancient world, but of all time.
