Eruvin 15B

ורבי מאיר מטהר. וכותבין עליו גיטי נשים, ורבי יוסי הגלילי פוסל.

But R' Meir deems it pure. Likewise, one may write women’s bills of divorce on anything, even a living creature. But R' Yosei HaGelili invalidates a bill of divorce written on a living creature.

גמ׳ תניא, רבי מאיר אומר: כל דבר שיש בו רוח חיים אין עושין אותו לא דופן לסוכה ולא לחי למבוי, לא פסין לביראות ולא גולל לקבר. משום רבי יוסי הגלילי אמרו: אף אין כותבין עליו גיטי נשים.

Talmud: It was taught in a baraita that R' Meir says: An animate object may neither be used as a wall for a sukka, nor as a side post for an alleyway, nor as one of the upright boards surrounding a well, nor as the covering of a grave. They said in the name of R' Yosei HaGelili: Nor may one write women’s bills of divorce on it.

מאי טעמא דרבי יוסי הגלילי, דתניא: ״ספר״, אין לי אלא ספר. מניין לרבות כל דבר? תלמוד לומר ״וכתב לה״, מכל מקום. אם כן מה תלמוד לומר ״ספר״? לומר לך: מה ספר דבר שאין בו רוח חיים ואינו אוכל, אף כל דבר שאין בו רוח חיים ואינו אוכל.

The Talmud asks: What is the reason for R' Yosei HaGelili’s opinion? As it was taught in a baraita with regard to the verse: “When a man takes a wife, and marries her, then it comes to pass if she finds no favor in his eyes, because he has found some unseemly thing in her; that he write her a scroll of severance and give it in her hand, and send her out of his house” (Deuteronomy 24:1): From the word scroll, I have derived that only a scroll is valid. From where is it derived to include all objects as valid materials upon which a bill of divorce may be written? The Torah states: “That he write her,” in any case, i.e., any surface upon which the formula can be written. If so, why does the verse state “scroll”? To tell you that a bill of divorce must be written on a surface like a scroll: Just as a scroll is neither alive nor food, so too, a bill of divorce may be written on any object that is neither alive nor food. That is why R' Yosei HaGelili invalidates a bill of divorce written on a living being.