one must apprehend that it was nibbling in a pre-existing hole! — He replied: How can you compare what is forbidden ritually with what is forbidden on account of possible danger to life! In the latter case we are certainly more apprehensive. Said Raba: What difference is there? Whenever there arises a doubt concerning a prohibition based on danger to life the stricter view is preferred, and the same is the case with regard to a doubt in connection with a ritual prohibition! — Said Abaye to him, Is there then no difference between laws concerning danger to life and laws concerning ritual prohibitions? But let us see! Whenever there is a doubt regarding any object whether it is clean or unclean, if such doubt arose in a public place, it is deemed clean; but whenever there is a doubt regarding water that was left uncovered it is deemed to be forbidden. He answered: In the case of uncleanness the rule is derived by analogy from the case of a woman suspected of adultery, viz., as [the doubt in connection with] the suspected woman can only occur in a private place. so [every doubt in connection with] uncleanness must have occurred in a private place. R. Shimi raised an objection: [We have learnt:] If a weasel has a [dead] reptile in its mouth, and walks over loaves of terumah, and it is doubtful whether the reptile came into contact with the loaves or not, they are deemed clean. Yet in the case of water left uncovered, if there is any doubt about it, it is forbidden? — Here again, the rule [in the case of uncleanness] is derived by analogy from the case of a woman suspected of adultery, viz., as [the doubt in connection with] the suspected woman [relates to a person that] has understanding to be questioned about it, so every doubt in connection with uncleanness must relate to such as have understanding to be questioned about it. Come and hear: If a man left uncovered a bowl [containing purification water] and came and found it covered, it is regarded as unclean, for I can say that an unclean person entered and covered it. If he left it covered and came and found it uncovered, and a weasel or, even a snake, according to R. Gamaliel — could have drunk from it, or if dew fell on it during the night. the water is invalid. And R. Joshua b. Levi said: What is the reason for this?14ᵃᵇᶜᵈᵉᶠᵍʰⁱʲᵏˡᵐⁿ