Reference for Eruvin 185:2

א"ל אביי לדידי כשירה לדידך סילוק מחיצות היא

is valid as a sukkah;<span class="x" onmousemove="('comment',' Suk. 18a.');">⁵</span> but if its side-posts had been straightened,<span class="x" onmousemove="('comment',' By putting up walls that covered them (cf. diagram supra mut. mut.) so that only two walls remained.');">⁶</span> it would have been invalid, would it not? '<span class="x" onmousemove="('comment',' Which is another case where a partition is the cause of a prohibition,');">⁷</span> 'According to my view, Abaye replied: 'it<span class="x" onmousemove="('comment',' Even in the absence or concealment of the side-posts.');">⁸</span>

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