Do you believe that seven is a lucky number or that things happen in sets of three? If so, your ideas are as old as Pythagoras, a Greek philosopher who lived 2600 yeara ago. Pytagoras, believed that certain numbers and their multiples had mystical power. For centuries, people have given importance to numbers and developed superstitions about them. Many of these superstitions have been passed on through the generations and still exist today.any of the superstitions surrounding numbers have a basis in science and nature. For example, early astrologers believed that seven planets governed the universe and therefore the lives 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 bring great change. If a person’s date of birth could be divided by 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.