Reference for Gittin 102:5

מאי קטן גדול ואמאי קרי ליה קטן דלגבי מילי דאביו קטן הוא

The presumption is that a man will not be brazen enough in the presence of his creditor [to deny a debt outright]. Now this man would like to deny the whole, and the reason why he does not deny the whole is because he is not brazen enough.<span class="x" onmousemove="('comment',' Hence when he acknowledges part, he is not trusted in regard to the rest. ');">⁵</span>

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