Reference for Bava Kamma 70:15

לא סיפא ניזק שמא ומזיק ברי רישא ניזק ברי ומזיק שמא

It would therefore seem that it was the plaintiff who was doubtful<span class="x" onmousemove="('comment',' In which case the argument contained in the preceding note could no more be maintained. ');">¹¹</span>

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