The incisive allusions come from The Sage Wang Xizhi.
Now people use the idiom "straight to the point" to describe the profound and thorough analysis of problems.
Wang Xizhi was a famous calligrapher in the Eastern Jin Dynasty. His calligraphy is elegant and beautiful, vigorous and unique, enjoying the reputation of "calligrapher".
Legend has it that Wang Xizhi once inscribed words on a plaque, and later hired a carpenter to engrave the words. Unexpectedly, the carpenter cut the board layer by layer, and finally found that Wang Xizhi's ink penetrated all the way to the depth of the board, which was three points thick. Cardboard is not paper, so it has good water absorption. The carpenter marveled at Wang Xizhi's vigorous calligraphy and perfect technique. So this matter was left as a much-told story, which has been used ever since.