  An ontological reading can accommodate the theory that heaven and earth and the “ten thousand things” are all constituted by qi. The decisive difference is that on this account, human beings all share the same essential nature, as distinguished from their qi-constituted capacities. For example, some people may be better endowed and therefore could live to a ripe old age, while others with a poorer endowment may die prematurely; but this does not detract from the fundamental assertion that they share the same inherent de, which defines their nature.