Ancient Greek mathematician and inventor Archimedes (c. 287–211 BCE) is best known for his discovery of the relation between the surface and volume of a sphere, as well as a hydrostatic principle known as the Archimedes principle. He also defined the principle of the lever in his work On the Equilibrium of Planes. Archimedes is quoted as having said, “Give me a place to stand and with a lever I will move the whole world.” This phrase is taken to express the idea that, given a firm footing and the proper tools, anything can be made possible.