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rupa (form)
visible objects (i.e. color and form)
「色」 has other readings with different meanings.
色即是空と経に書いてある。
The sutra says form is emptiness.
仏教では色は物質的な存在を意味する。
In Buddhism, rupa means material existence.
色と空の関係について学んだことがあります。
I have studied the relationship between form and emptiness.