A
tradesman who resides outside of a town in which his type of business
has already been established can be barred from plying his trade in
that town.
Rav Dimi, a Sage, brought his figs to
a town which wanted to give him exclusive trading rights. They sent Rav
Adda bar Abba to test him. He asked, “If an elephant swallows a
willow-reed basket and then ejects it through its rectum, is it
susceptible to ritual impurity or is it like manure? Rav Dimi didn't
know, so Rav Adda patronized him. Rav Dimi's figs spoiled, and Rav
Adda died. Every Sage involved took the blame for Rav Adda's death on
himself – because they wanted to discharge their karmic debt.
One who builds a wall opposite the
windows of his neighbor's house must ensure that the wall is either
higher or lower than the windows, so that he can't stand up on it nor
hang from it to look inside.