Reference for Bava Batra 10:2

תנן בחזקת שנתן עד שיביא ראיה שלא נתן

We have learnt: EACH IS PRESUMED TO HAVE GIVEN HIS SHARE UNTIL THE OTHER BRINGS PROOF THAT HE HAS NOT GIVEN. How are we to understand this? Are we to suppose that he says to the claimant: I paid when the payment was due?<span class="x" onmousemove="('comment',' Viz., when the wall reached a height of four cubits. ');">²</span>

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