Related על ביצה 1:3

R. Shimon ben Elazar said: The house of Shammai and the House of Hillel agrees that a ladder may be carried away. What did they disagree about? about bringing back, the house of Shammai forbids it, but the House of Hillel allows it. R. Yehuda says: Azariah says: One may move the ladder. In which case are these words said? In case the ladder of a dovecote. But in relation to a ladder which leads to the upper floor, it is forbidden to move them, even on the upper floor. R. Dosa says you can tilt one hatch to the other. Other sages said in the name of R. Dosa: They may also be brought near. R. Shimon says: the House of Shammai says: No one shall take a young pigeon unless he has tied it; but the house of Hillel says: Unless he shook it.