Just as if he ate two portions of cheilev fat in one lapse of awareness he is liable to only one chatas, so when the transgression is not known he brings only one asham talui. [But] if there was awareness in the interim, just as he brings a chatas for each one, so does he bring an asham talui for each one. Just as if he ate cheilev, blood, nossar, and piggul in one period of forgetfulness, he is liable for each one, so when the transgression is not known, he must bring an asham talui for each one. [If] cheilev and nossar were before him, and he ate one of them, but it is not known which of them he ate; [or if] his menstruous wife and his sister were with him in the house, and he inadvertently cohabited with one of them, but it is not known with which one of them he inadvertently cohabited; [or if] the Sabbath and Yom Kippur [followed one another], and he performed labor at twilight, but it is not known on which of them he performed [labor] — R’ Eliezer holds [him] liable to a chatas, but R’ Yehoshua exempts [him]. Said R’ Yose: They did not disagree that one who performed labor at twilight is exempt, for I may say that he did part of the labor today and part of it tomorrow. Concerning what did they differ? Concerning one who performed [labor] in the middle of the day, but it is not known whether he did it on the Sabbath or on Yom Kippur, or concerning one who performed [labor], but it is not known what type of labor he did. R’ Eliezer holds [him] liable to a chatas, but R’ Yehoshua exempts [him]. Said R’ Yehudah: R’ Yehoshua exempted him even from an asham talui.