The first number is 6, which means "six-dimensional theory". This theory proves that "anyone can get in touch with anyone in the world with only six people at most".

The objective interpersonal network is a six-dimensional space.

The law of "six dimensions" says: regardless of country, nationality and age, you and any stranger in the world are separated by only six people who know each other on average.

The second number is 150, and 150 is the famous Dunbar number. The law infers that "the number of people allowed to have a stable social network by human intelligence is about 150".

150 law was discovered by anthropologist Robin Dunbar of Oxford University in 1990s. Human cerebral cortex? The memory is too small. Everyone can only have 150 friends at most. The definition of friends here is to contact at least once a year. What is more tragic is that a person's friends in his life will rapidly shrink to an average of about 20.

The third number is 5, which can also be called the "five-person law". Jim Ron, the founder of a famous American successful school, famously said, "Your income is the average income of the five people who have spent the longest time with you."