THE RENDERING OF AN ALLEY FIT [FOR THE MOVEMENT OF OBJECTS WITHIN IT ON THE SABBATH], BETH SHAMMAI RULED, REQUIRES A SIDE-POST AND A BEAM, AND BETH HILLEL RULED: EITHER A SIDE-POST OR A BEAM.
The question is are these just symbolic or are they substantial? The size and width of the side posts are argued. Whether one or two are necessary is argued. And much might be dependent on the size of the alley.
And it’s shape.
R. Nahman stated: ‘We have a tradition that if [the movement of objects in] an alley is to be permitted [on the Sabbath] by means of a side-post and a cross-beam, its length must exceed its width
This would exclude square shaped alleys. This is a courtyard! Alleys and courtyards are treated differently.
Only one that is square shaped but not one that is round?
Guess not. Apparently there is no such thing as a circular alley!
And [by] how much [must its length exceed its width]?
Samuel intended to rule: By no less than twice its width; but Rab said to him: Thus ruled my uncle ‘Even by one fraction’.
Turn your square into a rectangle and leave your circle alone. Isn’t geometry fun!