Many of the superstition surrounding numbers have a basis in science and nature. For example, early astrologers believed that seven planets governed the universe and therefore the lines of human beings. A seventh child was thought to have special gifts. Human life was divided into seven ages. Every seventh year was believed to seven, that person’s life would be lucky. For the ancient Babylonians, three was a lucky number because it symbolized birth, life, and death. Some people still believe that a dream repeated three times comes true.