Replied R’ Akiva to him: Your words are acceptable in the case of a small me’ilah. [But] what if he is guilty of a doubtful case of me’ilah of one hundred maneh, is it not better for him that he bring an asham for two selaim and not bring a doubtful restitution of one hundred maneh? R’ Akiva [then] agrees with R’ Tarfon in the case of a small me’ilah. [If] a woman brought a bird chatas of doubt: If it became known to her before its neck was nipped that she had definitely given birth, she must make it an unconditional [chatas], for, from the [same] species from which she brings for an obligation of doubt, she brings for an obligation of certainty.