The question
Why do people pay more for phone numbers and addresses full of 8s?
The short answer
In Chinese, the word for eight sounds like the word for prosperity. That sound-alike made 8 the luckiest number across much of East Asia, and markets have measured people paying for it.
What science knows
Cultural TraditionIn Mandarin, eight (bā) sounds close to fā (發), as in fācái, to become wealthy; in Cantonese the pair is baat and faat. The Beijing Olympics opened on 8 August 2008, at 8:08 in the evening.
Eight is significant in other traditions too: the Buddhist Noble Eightfold Path, and the eight days of Hanukkah.
The pattern
Established Mathematics8 is 2³, the first cube after 1, and a Fibonacci number. In music, the eighth note of a major scale completes the octave, a 2:1 frequency ratio. In chemistry, many atoms are most stable with eight outer electrons, the octet rule, which has exceptions.
What is still uncertain
Mixed EvidenceStudies of Hong Kong’s licence-plate auctions found that plates with lucky digits such as 8 sold for more, and unlucky 4s for less. How large these effects are elsewhere, and how they change as markets grow, varies between studies.
Why humans find it interesting
Cultural TraditionThe same logic makes 4 unlucky in China, Japan and Korea, because it sounds like the word for death; some buildings skip the fourth floor.
CUE perspective
CUE PerspectiveIn CUE, 8 is strongly associated with money and karma, a meaning that sits alongside the Chinese tradition without being the same thing.
CUE’s reading is its own framework. The culture explains why 8 feels lucky to so many people; the mathematics explains why it keeps turning up.