天常

Etymology
天 (天生 - natural) + 常 (五常 - the five unchanging relationships)
 * According to traditional Confucianism, there were five kinds of human relationships (五常) which followed natural (天生) laws and were unchanging:
 * ruler and subject (君臣)
 * father and son (父子)
 * husband and wife (夫婦)
 * older brother and younger brother (兄弟)
 * friends (朋友)

Noun

 * 1)  the natural order of things; the natural hierarchy of human relationships