楊屾（1699-1794）號雙山，陝西興平縣人。他在歷史上主要以農桑專業被表揚與紀念。然而，楊屾的思想體系龐大，遠超出農桑之學的範圍。他吸收了天主教或伊斯蘭教的觀念，創造出自己獨特的思想。為了說明楊屾有機會接觸天主教或伊斯蘭教，本文首先介紹明末清初陝西地區的伊斯蘭教與天主教的發展。接著，透過解讀楊屾的重要著作《知本提綱》說明他的思想系統，指出無論是人格上帝、創造論、人間秩序觀，或是對死後的想像，包括靈魂不朽、靈魂將依是否克盡倫職而接受賞罰，有類似天堂與地獄的觀念等，都顯示楊屾思想雜糅儒學與外來宗教的元素。最後，本文亦試圖比較楊屾思想與天主教及中國伊斯蘭教，說明楊屾固守儒學之處，並分析其學具有儒學庶民化與宗教化之意涵。

Yang Shen (1699-1794) was a Shaanxi scholar renowned for his knowledge and achievements in sericulture, which also dominate the existing scholarship about him. Yang Shen's works, however, reveal much wider concerns beyond agriculture and demonstrate a highly inclusive system of thought that synthesized Confucianism and Christianity or Chinese Islam. To ascertain the availability of Christian and Islamic knowledge to Yang Shen, this paper first briefly discusses the history of Islam in China, especially in Shaanxi, and the development of Christian missions in Shaanxi during the early Qing.It then proceeds to study Yang Shen's thought based on a close reading of his work ”Zhiben tigang” (An Outline of Knowledge of Essential Principles). There is no modern reprint of ”Zhiben tigang”. Even though it has been little noticed in modern scholarship, it represents significant elements of the intellectual tapestry of the eighteenth-century China. By focusing on ”Zhiben tigang”, this paper elaborates on Yang Shen's ideas, including the creation of the universe by a personal God, the concept of personal soul, the similar principles between the invisible spiritual world and the concrete visible world, the ideal political and social orders, the duties of life, and the imagination of an afterlife. It also compares Yang Shen's thought with Christianity and Chinese Islam, expounds on the popular religious connotations in Yang's Confucian thought, and discusses both the innovations and limitations in Yang's thought in terms of personal salvation, gender equality, and political rights.