Quickly 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 the second half of “תוס’ “קל וחומר starting from “ואמחיצה רביעית”
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?
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. The Brisker Rav said that the קל וחומר is only needed to teach us that עמוד מרובה is an acceptable Tikun of the fourth side and we view it as closing the fourth side. How could Tosfos entertain the idea that we could learn that עמוד מרובה should work for the other three sides?
Learn מהרש”א
https://hebrewbooks.org/pdfpager.aspx?req=14312&st=&pgnum=263
In conclusion, is עמוד מרובה accepted for the other three sides of a Mavui?
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
Clarify the Tikunim of chatzer and mavui according to Tosfos.
Question:
Tosfos says that עמוד מרובה is accepted on the other three sides of a Mavui. This is contradiction to Tosfos above who said we can not learn that from the ק”ו?
Learn “תוס’ רבינו פרץ “אבל במבוי