Sir Isaac Newton was an English physicist and mathematician who is considered one of the greatest scientists of all time. He developed the laws of motion and universal gravitation, which dominated the scientific view of the physical universe for the next three centuries. Newton was influenced by scientists like Galileo and Kepler but was frustrated by arguments with fellow scientists like Robert Hooke. Newton helped change the Western worldview by establishing the principles of modern physics and proving the universe followed predictable mathematical rules rather than religious or mythical explanations.