己jǐ

己 (jǐ), the sixth of the Heavenly Stems, appears in Simplified Chinese as it has for millennia — its form in oracle bone and bronze script depicted twisted thread or silk, suggesting the idea of binding or oneself. As a radical, it lends its shape to characters like 巷 (alley) and 巽 (a trigram), while its meaning of "self" lives on in words like 知己 (confidant) and 知己知彼 (know yourself and know your enemy).