1.
Yoram Rovner asked:
What is the meaning of this Rashi? That without a rebiit of dam a man dies or that a man needs at least a rebiit to live?
Thanks
Yoram Rovner, Santiago, Chile
2.
The Kollel replies:
A man needs at least a Revi'is Dam to live (see Rashi at the end of Shabbos 31b).
Actually, the Rambam writes that, like all other Shiurim, this Shiur is a Halachah l'Moshe m'Sinai.
D. Zupnik