Both 气 and Shinjitai kanji 気 are simplified forms of the traditional character 氣. Uncle Hanzi says that it could have been a depiction of (a man) blowing 气 on (presumably just cooked) rice 米. Ponte Ryūrui points out that
the ancient 气 is not the same character as modern simplified Chinese 气. The former is a pictograph of a breath in the form of vapour, as observed on a cold day, whereas the latter is a simplification of 氣.In any case, since the symbol for rice could be either present or absent from the character, I’d suggest we forget about rice for now and simply try to remember that 气 is about blowing.
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