Review the גמרא דף ה: “אמר רב הונא (eight lines from top of the Amud) until “רב אשי אמר (seven lines from bottom of the Amud)
Review “תוס’ “קל וחומר
Major Question:
The concept of עמוד מרובה is a halacha l’moshe misinai in the laws of mechitza. Why should we need a קל וחומר from חצר to teach us it is considered a valid wall for the fourth side of a Mavui?
Why is עמוד מרובה not accepted for the other three sides of a Mavui especially when we see it works by a חצר?
Yesterday we discussed the explanation of the Brisker Rav (גרי”ז בכורות דף יז עמוד ב “והנה בעירובין) that Rabanan made a tikun on the fourth side of a Mavui that it needs to be considered closed. Therefore the קל וחומר is needed to teach us that עמוד מרובה besides being considered a mechitza is also viewed as closing the fourth side.
Tosfos says although עמוד מרובה is acceptable for a Chatzer on all four sides we can only learn from a קל וחומר to Mavui that it should be valid for the fourth side. Why?
In conclusion, is עמוד מרובה accepted for the other three sides of a Mavui?
Learn מהרש”א
https://hebrewbooks.org/pdfpager.aspx?req=14312&st=&pgnum=263
Learn מהרש”א מהדורא בתרא
https://hebrewbooks.org/pdfpager.aspx?req=14312&st=&pgnum=296
Learn שפת אמת על תוס’ “ק”ו
https://hebrewbooks.org/pdfpager.aspx?req=14521&st=&pgnum=187
Question:
Does a פס ד need to be recognizable that it was placed there to be a tikun for the Chatzer or Mavui?
Learn “תוס’ “אינו
Learn תוס’ רבינו פרץ “אבל במבוי