Firstly I reject your premise that Chinese people are less altruistic than Western people. It's clear to me from your remarks you have not spent much time in China. One could point to the need for contractualisation of every transaction in Western society even sometimes between family members as an example of the core difference in attitude. As a thought experiment, consider a society where legal contracts were not enforceable. Everything must be executed on the basis of trust. People would develop networks of trust that would become highly interconnected and thereby self-enforcing. If you don't take the time to ingratiate yourself into these networks, you are, with good reason, not to be trusted. If on the other hand, you do take the time to do so, so much can be achieved without formalisation, much can be forgiven, strangers become trusted friends and the focus shifts from transactions between individuals to long term trust and friendship. Historically there are reasons why the legal contract evolved as a primary enabler of transactions in Western Europe but not in China. I suggest you read some history of contract law.