The moral characters of humans endowed or influenced by qi (气) stand in contrast with “characters endowed by Heaven” or “characters endowed by Heaven and Earth.” The term encompasses two meanings. First, it refers to the specific disposition of a person under the influence of qi, such as firmness and gentleness, patience and impatience, and wisdom and stupidity. In this sense, the “character endowed by qi” and the “character endowed by Heaven” together constitute a person’s inborn character. Second, it means that heavenly laws and qi together influence a person’s character. As heavenly laws are imbedded in the physical human body, they are influenced by qi. The interaction of moral characters endowed by heavenly laws and human desires reflects the “character endowed by qi (vital force).”

Physical matters take up their shape which acquires the nature of qi (vital force); if we are thus good at returning to it, then the nature endowed by heaven and earth will be preserved. (Zhang Zai: Enlightenment Through Confucian Teachings)

As for the properties of heaven and earth, they refer exclusively to heavenly laws. As for the nature of qi, it refers to the combination of heavenly laws and qi. (Categorized Conversations of Master Zhu Xi)