The Shijing line 如切如磋, "as if cut, as if polished," gets glossed in the Mao commentary as 骨謂之切, "to work bone is called 切. " Cutting where the thing wants to part. Uragiri names the geometry of trust before the wound. You only cut a lining if someone lets you near; you only cut at the joint if you know where it is. The print above is the textbook uragiri: the Honnō-ji incident of 1582, when Akechi Mitsuhide cut down his master Oda Nobunaga at the moment of greatest trust. 例: 友達に裏切られた。