折疑論 2.147

2.147

是以君子之於禽獸也。見其生不忍見其死。聞其聲不忍食其肉（孟子曰。齊宣王釁鐘以羊易牛。二者。得其兩全無害。以為仁之稱也。聲謂將死而哀鳴也。蓋人於禽獸同生而異類。故用之以禮。而不忍之心不可施於見聞）。

Hence, toward birds and beasts, the noble person, 'having seen them alive, cannot bear to see them die; having heard their cries, cannot bear to eat their flesh' (Mencius says: King Xuan of Qi consecrated a bell by replacing an ox with a sheep; both were preserved without harm, which is called humaneness. 'Cries' refers to mournful crying when approaching death. Humans and animals share life but belong to different categories; therefore one treats them with propriety, and one's unbearing mind cannot bear to witness or hear their deaths).