Hangul
Hangul drew its consonants from the shape the mouth makes and its vowels from sky, earth, and human being. Add a stroke and the sound hardens. Twenty-eight letters cover that many sounds not because more letters were added, but because a rule for combining them was designed.
| First tell — Structure | The consonants came from the shape the mouth makes to produce a sound; the vowels from sky, earth, and human being. Add a stroke and the sound hardens. One stroke turns ㄱ into ㅋ. |
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| Second tell — Purpose | The preface says it was made out of pity for people who could not put their meaning into writing. Easy to learn was the design condition. It is a rare case where the purpose survives as a document. |
| Third tell — Order | Twenty-eight letters carry that many sounds. Few letters covering a wide range came not from adding more letters, but from designing a rule for combining them. |
The shape inside a mouth became a letter. A design that made sound visible.