(א) אֵלּוּ מְצִיאוֹת שֶׁלּוֹ, וְאֵלּוּ חַיָּב לְהַכְרִיז. אֵלּוּ מְצִיאוֹת שֶׁלּוֹ, מָצָא פֵרוֹת מְפֻזָּרִין, מָעוֹת מְפֻזָּרוֹת...
(1) In a case where one discovers lost items, which found items belong to him, and for which items is one obligated to proclaim his find so that the owner of the lost items can come and reclaim them? These found items belong to him: If one found scattered produce...
Rav Ukba bar Hanna was a 4th generation Babylonian Amora.
Rabbi Yirmiya was a 3rd/4th generation Amora from the Land of Israel. He was the student of the students of Rabbi Yohanan.
An object whose ownership has been renounced; an ownerless object. As a verb, the act of declaring an object ownerless.
Steinsaltz Reference Guide: Lit., establishing. An interpretation of a Mishnah or Barraita which “establishes” it as referring to a particular case or following a particular viewpoint is called an אוֹקִימְתָּא. (pp. 99-100).
וכמה א"ר יצחק קב בארבע אמות - צריך לומר דרבי יצחק גופיה בעי וכמה דאי גמרא בעי מאי בעי וכמה לוקי דרך נפילה ואפילו טובא כדפריך גמ' בתר הכי אלא מדברי רבי יצחק הוא...
We must say that it was Rav Yitzhak himself who asked “and how much?” (and not the stamma degemara).
Because if the gemara asked–why would it need to ask?
It has already established that [the scattered fruit belongs to whoever finds it] based on how the fruit falls.
In which case even it would belong to the finder even if it was more than a kav worth of fruit
Which the gemara used as a challenge to Rav Yitzhak...