Word-for-word 'not speak / from-itself / clear' — 'without being said, it's clear on its own.' Used in formal speech and writing to mark a conclusion the speaker thinks is obvious. Often interchangeable with
显而易见 (xiǎn'éryìjiàn, 'plainly obvious') and
不言而喻 (bùyán'éryù, 'understood without being spoken') — the last is closest in meaning and slightly more literary.