Getting a bit off-topic, but I also wanted to take the time here to talk about the mandate of heaven (天命), an old concept of Chinese political philosophy. I think it's a good precursor to the modern Chinese understanding of democracy and the legitimacy of governments.

The mandate of heaven is a concept that was invented to explain why imperial dynasties rise and fall. It essentially states that a dynasty has divine favour and a mandate to rule if it rules in a manner that is fair and just, and benefits the people. When a dynasty becomes corrupt and unjust in its rule, the mandate of heaven will be withdrawn and the people will revolt against it, and a new dynasty will rise up and replace it.

The concept is inherently steeped in traditional Chinese religious practices and beliefs which mostly are no longer relevant today. But I think that the mandate of heaven is nothing more than a religious way of spelling out the concept of popular sovereignty. When a dynasty rules for the benefit of the people, it enjoys the mandate from heaven. In modern political thought, we understand that a government instead derives from the people directly. But other than that, it's the same thing.

The Communist Party claimed its mandate during the Chinese Civil War when it overthrew the old dynasty (Chiang Kai-Shek) and established a new one (Mao Zedong). And as long as it continues to enjoy popular support, it has that mandate to rule. I do note that notwithstanding all of this text, both men would have found it insulting to be referred to as the leaders of a dynasty. But what was then called a dynasty is now called a republic. The fact that the post of chief of state, be it emperor, president, or general secretary, is no longer hereditary, has no bearing on the fundamental nature of it.