佛說處處經 1.72

1.72

佛言：「阿羅漢不食肉者，計畜生從頭至足，各自有字無有肉名。辟支佛計本精所作不淨，故不食肉。佛計一切天下皆空無所有，有便滅，滅復生，要歸空故，為無所有。」諸弟子聞經歡喜，為佛作禮而去。

The Buddha said: "As for why an arhat does not eat meat: he calculates that an animal, from head to foot, each part has its own name, and there is no entity named 'meat'. A pratyekabuddha calculates that it is made from the original semen and is impure, and therefore does not eat meat. A Buddha calculates that everything under heaven is empty and has nothing; what exists is immediately extinguished, and what is extinguished is born again, ultimately returning to emptiness, and therefore is devoid of existence." All the disciples, having heard the sūtra, rejoiced, bowed to the Buddha, and departed.