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 years ago. Pythagoras believed that certain numbers and their mutiples 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.
Many 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.
Numbers don't have the same meaning in all cultures. Five is considered a most holy and lucky number in Egypt. But in Ghana, the Ashanti people consider five to be an unlucky number. To give someone five of anything is to wish the person evil. The ancient Greeks amd Egyptians thought the number four was a perfect number symbolizing unity, endurance, and balance. However, the Chinese consider the number four to be unlucky because it sounds like the word for death.
The number that seems to be almost universally considered unlucky is 13. No other number has had such a bad reputation for so long. The ancient Romans regarded it as a symbol of death, destruction, and misfortune. One of the earliest written stories about the number 13 appears in NOrwegian mythology. This story tells about a feast at Valhalla to which 12 gods were invited. Loki, the god of evil, came uninvited, raising the number to 13. In the struggle to throw out Loki, Balder, the favorite of the gods, was killed.