Neo-Confucianism may be seen as a grand attempt to articulate a morally ordered cosmos in which inner cultivation and outer responsibility are inseparable. At its core stand the paired concepts of **li** and **qi**. Li is the universal, rational principle that underlies all things, the normative pattern that gives form, order, and moral direction to existence. Qi is the dynamic, material force or vital energy through which li is expressed, the psychophysical “stuff” that constitutes the phenomenal world. Everything is understood as a particular configuration of li realized in qi, so that moral order is not an arbitrary human construct but grounded in the very structure of reality.

This vision is deepened by the idea of the **Supreme Ultimate (Taiji)**, the highest li and the ultimate source from which yin–yang and the myriad things emerge. Taiji represents the unity that underlies cosmic dualities and the ongoing processes of change, allowing a rich cosmology without recourse to a creator deity. Within this framework, human beings occupy a privileged place: they participate in the same li that orders Heaven and Earth, and thus their ethical life is continuous with the structure of the cosmos. The traditional Confucian emphases on ritual propriety, humane governance, and ordered relationships are thereby given a metaphysical foundation.

Human nature (**xing**) is affirmed as inherently good, rooted in li itself. Moral failings are attributed not to a corrupt principle but to obscurities and disturbances in qi, which cloud the original clarity of the mind–heart. Within this nature lie the “Four Beginnings” of benevolence, righteousness, propriety, and wisdom, which, when properly cultivated, blossom into full virtue. Self-cultivation thus becomes the central task: through rectifying the mind, practicing sincerity and integrity, and engaging in ethical conduct, one seeks to restore and manifest the goodness already present at the deepest level.

The method of **self-cultivation** is closely linked to the **investigation of things (gewu)** and the extension of knowledge. By carefully studying texts, rituals, natural phenomena, and social relations, one seeks to discern the li that structures them, combining empirical attention with moral reflection. This process is not merely intellectual; genuine understanding of li is expected to transform character and action, so that knowledge and practice mutually reinforce one another. In some influential interpretations, the mind itself is identified with li, and an innate moral knowing is said to be present in everyone, such that truly knowing the good already impels one to act upon it.

Neo-Confucian thinkers drew deeply from Buddhist and Daoist currents while sharply criticizing aspects they found incompatible with an engaged ethical life. From Buddhism they adopted a refined concern with inner transformation, meditation, and moral psychology, yet they rejected world-denial and monastic withdrawal as ultimate ideals. From Daoism they absorbed cosmological patterns such as yin–yang and an appreciation of natural processes, while resisting quietist tendencies that might neglect social and familial obligations. The result is a vision in which Heaven, Earth, and humanity form a single moral–cosmic order, and in which the path to sagehood lies in harmonizing one’s mind–heart, conduct, and relationships with the ever-present li that pervades all things.