Reference for Bava Batra 71:12

והא איכא צפרא ופניא בנהרדעא טייעי שכיחי ומידא לידא משלמי:

[But surely] Resh Lakish has said that there is no <i>hazakah</i> to living things? Goats are an exception, because they are entrusted to a goatherd.<span class="x" onmousemove="('comment',' And therefore if they are found in another man's property, it is presumed that he has bought them. ');">²¹</span> But they are left to themselves morning and evening?<span class="x" onmousemove="('comment',' In the morning when they go by themselves from their owners to the goatherd, and in the evening when they go back by themselves from the goatherd to the owners. ');">²²</span>

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