自 zì is a pictograph of a nose. The oracle-bone and bronze forms draw a nose seen head-on, with the bridge down the middle and the nostrils marked below. The modern shape still holds that outline: read it as a little face with the nose at the center. The link to "self" is a gesture, not a metaphor. To this day a Chinese speaker pointing at the self touches the nose rather than the chest, and that habit is exactly how 自 came to mean me, oneself.

Because the nose sense drifted almost entirely into "self," the language built a new character for the body part, 鼻 bí (nose), which keeps 自 on top as a clue to both meaning and sound. So 自 is the original nose, and 鼻 is the replacement that grew up around it once 自 had gone abstract.

From the pointed-at self three senses branch out:

1. Self, oneself. The reflexive center: 自己 zìjǐ (oneself), 自我 zìwǒ (the self, the ego), 自由 zìyóu (freedom, literally self-determined).
2. From, since. The source a thing starts at: 来自 láizì (to come from), 自从 zìcóng (ever since), 自古 zìgǔ (since ancient times).
3. Naturally, of itself. Acting on its own accord, with no outside push: 自然 zìrán (nature; natural), 自动 zìdòng (automatic), 自发 zìfā (spontaneous).

The thread tying the three together is origin from within. The self is where a person starts; "from" marks where a path starts; and "of itself" describes an action that starts from a thing's own nature rather than from anything outside it.

The second life of 自 is as a marker of source. Here it means "from," naming the point a thing or a path begins at. With place it answers where something comes from: 来自北京 "comes from Beijing," 自远方 "from afar." With time it sets the start of a stretch: 自古以来 "from ancient times onward," 自小 "from childhood." In this sense 自 leans formal and literary, the written cousin of the everyday 从 cóng.

Watch the two faces of 自 at once and the link is clear. The self is where a person originates; "from" is where a journey originates. One nose, pointed inward, marks the origin of a person; the same character, pointed outward, marks the origin of a path.

The third sense of 自 is the most philosophical: a thing acting of its own accord, with no outside hand. The clearest case is 自然 zìrán, 自 (self) + 然 (so), literally "so of itself." It names both nature, the world that runs on its own, and the quality of being natural and unforced. In Daoist thought 自然 is a central ideal, the way things unfold when nobody is pushing them.

The same "of itself" underlies a family of modern words: 自动 zìdòng (automatic, moving by itself), 自发 zìfā (spontaneous, arising by itself), 自愿 zìyuàn (voluntary, willed by oneself). In each, 自 says the action comes from the thing's own nature rather than from compulsion, which loops the sense back to the self: what is self-driven is what acts from within.

Picture an ancient speaker raising a finger to the nose and saying "me." That gesture is the whole character: 自 is a drawing of a nose, and a nose pointed at means the self. The original "nose" job later moved to 鼻 bí, leaving 自 to carry only the abstract self.

From that pointed-at nose, fan out the three senses. Point inward and 自 is the self: 自己, 自由, 自信. Point at where a path begins and it is "from": 来自, 自从. Point at a thing that needs no outside push and it is "of itself": 自然, 自动. Every 自 traces back to one origin, the nose at the center of the face, the place where a person starts.