Sukkah 27A

ואמרו: העלום לסוכה.

and they each said: Take them up to the sukka.

וכשנתנו לו לרבי צדוק אוכל פחות מכביצה, נטלו במפה ואכלו חוץ לסוכה ולא בירך אחריו. הא כביצה, בעי סוכה. לימא תיהוי תיובתיה דרב יוסף ואביי! דילמא פחות מכביצה נטילה וברכה לא בעי, הא כביצה בעי נטילה וברכה.

And when they gave R' Tzadok less than an egg-bulk of food, he took the food in a cloth and he ate it outside the sukka and did not recite a blessing after eating it. The Talmud infers: Had they given him an egg-bulk of food, he would have been required to eat it in a sukka. Let us say that this is a conclusive refutation of the opinion of Rav Yosef and Abaye, who said that one is permitted to eat that measure in the context of a casual meal outside the sukka. The Talmud answers: No proof can be cited from here, because perhaps the reason the Mishnah emphasizes that R' Tzadok ate less than an egg-bulk of food is that eating less than an egg-bulk does not require washing hands and reciting a blessing after eating it; however, eating an egg-bulk requires washing and reciting a blessing.

מתני׳ רבי אליעזר אומר: ארבע עשרה סעודות חייב אדם לאכול בסוכה, אחת ביום ואחת בלילה. וחכמים אומרים: אין לדבר קצבה, חוץ מלילי יום טוב ראשון של חג בלבד.

Mishnah: R' Eliezer says: A person is obligated to eat 14 meals in the sukka over the course of the 7 days of the festival of Sukkot, one during the day each day and one at night each night. And the Rabbis say: There is no quota for the number of meals, and one may choose whether or not to eat any of the meals except for the meal on the evening of the first Festival day of Sukkot, which one is required to eat in the sukka.

ועוד אמר רבי אליעזר: מי שלא אכל [לילי] יום טוב הראשון ⁠— ישלים לילי יום טוב האחרון של חג. וחכמים אומרים: אין לדבר תשלומין, ועל זה נאמר: ״מעות לא יוכל לתקון וחסרון לא יוכל להמנות״.

And furthermore, R' Eliezer said: One who did not eat a meal on the evening of the 1st day of the Festival should compensate with a meal on the evening of the last day of the Festival, on the 8th Day of Assembly, despite the fact that he will not eat it in the sukka. And the Rabbis say: There is no compensation for this matter, and with regard to similar cases where it is impossible to rectify failure to fulfill a positive mitzva, it is stated: “That which is crooked cannot be made straight; and that which is wanting cannot be numbered” (Ecclesiastes 1:15).