自以为是
zì yǐ wéi shì · HSK 7
to believe oneself infallible
🦚 自 self + 以为 to assume + 是 right = assumes oneself is always right
Breaks down as 自 (self) + 以为 (to assume/suppose) + 是 (correct, right). The four together name someone who treats their own view as automatically correct: opinionated and self-righteous.
自 — pictograph of a nose
自 originally depicted a human nose, shown frontally with the bridge and nostrils. Ancient Chinese pointed to their own nose to mean 'me,' so 自 shifted to mean 'self' or 'oneself.' A new character 鼻 was later created to carry the original 'nose' meaning.
以 — phonetic 㠯 (plow/tool) + 人 (person)
Originally a pictograph of a hand-held plow or tool (㠯), later combined with 人 (person) to suggest 'using' something. The core meaning 'to use' extended metaphorically to 'by means of', 'with', and 'because of'. In modern Chinese it functions mainly as a grammatical particle.
为 — simplified form of 為; from 爪 (claw/hand) over 象 (elephant)
The traditional form 為 originally depicted a hand leading an elephant, suggesting the act of doing or making work. Over time it generalized to mean 'to do, to act, for the sake of.' The simplified 为 preserves this 'do/for' meaning, with pronunciation shifting between wéi ('to be, to do') and wèi ('for, because of').
是 — sun 日 + 正 (correct/upright)
Originally a compound suggesting 'the sun 日 directly overhead'—straight, correct, true. From this concrete sense of 'right' or 'this very thing,' 是 came to mean 'this' as a demonstrative, and later the modern copula 'to be / is.' The 'correct' meaning survives in words like 是非 (right and wrong).