Terminology: Karpef! (finally). Also, the case if the karpef near the home of the Resh Galuta. Who, in the end, has harsh words for the sages Andrew their figuring and configuring of the eruv. We see some of the tension between the political power, as compared to the sages themselves, in Babylonia, specifically. Plus: Comparing the verse used to criticize the sages to its meaning in its original context (Jeremiah). Also: When the group of people in homes on a courtyard join together to make an eruv on that area, and one person/family does not participate in the eruv - how can that person carry in the courtyard? By relinquishing ownership over the courtyard, which allows the rest of the cooperative (for this purpose specifically) to host that person/family as a guest. And a second comparable version of the case, used to flesh out R. Eliezer's view that one relinquishes ownership of the home as well. We see creativity in the loopholes, and the practicality of them.