Huai Su's Autobiography, scribed in 776 AD by Buddhist monk Huai Su (725–785 AD), is considered one of the finest cursive script works in Chinese history. The original is lost, but three modelling copies existed; the Shu version is deemed superior to the Su version held at the National Palace Museum in Taipei for its artistic variability and consistency with Huai Su's style. Huai Su's cursive script tradition traces back to Han Dynasty calligraphers and was influenced by his discourse with Yan Zhenqing.