- At every village level they have "informants" for the communist party who inform their higher ups regularly about village level activity. They are financially supported with healthcare and education subsidies and so it makes sense for everyone to join in and inform, especially the poor.
- At the city level they have more ways to collect information about people like companies feeding data bases, people interacting with the internet and retail.
He explained that the idea is even if 10% of the population is brain washed they can keep tabs on the 90% and when shit hits the fan they want to be in the know. After Tiananmen they have followed a formula: Keep enough people happy and conforming with economic prosperity and get ahead of the curb for restive remainder.