Numerology
Numbers play a prominent role in Chinese beliefs about luck. Even numbers and pairs are often considered lucky, and are associated with positive energy or "qi." Exceptions occur when the word for a number sounds like something else. For instance, the word for four sounds like the word for death and is therefore avoided, whereas the word for the number three sounds a lot like the word for life and so is considered good. Nine is considered among the luckiest of numbers, signifying happiness and long life.