Eruvin — Daf 90b

דהא איכא מחיצתא ושמואל אמר אין מטלטלין בה אלא בארבע אמות מחיצות להבריח מים עשויות

אמר ליה רב חייא בר יוסף לשמואל הילכתא כוותך או הילכתא כרב אמר ליה הילכתא כרב

אמר רב גידל אמר רב חייא בר יוסף ומודה רב שאם כפאה על פיה שאין מטלטלין בה אלא בארבע אמות כפאה למאי אילימא לדור תחתיה מאי שנא מגג יחידי

אלא שכפאה לזופתה

רב אשי מתני לה אספינה ורב אחא בריה דרבא מתני לה אאכסדרא דאיתמר אכסדרה בבקעה רב אמר מותר לטלטל בכולה ושמואל אמר אין מטלטלין בה אלא בארבע

רב אמר מותר לטלטל בכולה אמרינן פי תקרה יורד וסותם ושמואל אמר אין מטלטלין בה אלא בארבע לא אמרינן פי תקרה יורד וסותם

ורב אליבא דר"מ ליטלטלי מגג לחצר גזירה משום דרב יצחק בר אבדימי

ושמואל אליבא דרבנן ניטלטל מגג לקרפף אמר רבא בר עולא גזירה שמא יפחת הגג

א"ה מקרפף לקרפף נמי לא יטלטל דילמא מיפחית ואתי לטלטולי התם אי מיפחית מינכרא ליה מילתא הכא אי מיפחית לא מינכרא מילתא

אמר רב יהודה כשתמצא לומר לדברי רבי מאיר גגין רשות לעצמן חצירות רשות לעצמן

because it has1 walls;2 ‘and Samuel ruled: Objects may be moved only within four cubits’, since the walls were put up for the purpose of keeping out3 the water.4 ‘Is the law’, R. Hiyya b. Joseph asked Samuel, ‘in agreement with your view or is it in agreement with that of Rab?’ — ‘The law, the other replied: ‘is in agreement with that of Rab’. ‘Rab’, explained R. Giddal in the name of R. Hiyya b. Joseph, ‘agrees nevertheless that if it was turned upside down5 objects on it6 may be moved only within four cubits. For what purpose, however, was it inverted? If it be suggested: For the purpose of dwelling under it, why, it could be objected, should its law be different from that of a single roof?7 — It was inverted rather for the purpose of being coated with pitch.8 R. Ashi reported9 this10 with reference to a ship; but R. Aha son of Raba11 reported it with reference to an exedra. For it was stated: If an exedra was situated in a valley, it is, Rab ruled, permitted to move objects within all its interior; but Samuel ruled: Objects may be moved within four cubits only. Rab ruled that it was permitted to move objects in all its interior because we apply the principle: The edge of the ceiling descends and closes up. But Samuel ruled that objects may be moved within four cubits only because we do not apply the principle: The edge of the ceiling descends and closes up. 12 But according to Rab's interpretation of R. Meir's view,13 should it not14 be permitted to move objects from a roof into a courtyard?15 This is forbidden as a measure16 of which R. Isaac b. Abdimi has spoken.17 And according to Samuel's interpretation of the view of the Rabbis,18 should it not be permissible to move objects19 from a roof to a karpaf?20 — Raba21 b. Ulla replied: The prohibition is due to a preventive measure against the possibility of a reduction in the area of the roof.22 But if so, it should also be forbidden to move an object23 from karpaf to karpaf24 since the area of one of them might happen to be reduced25 and people would still be moving objects from one to the other? — If a reduction were to occur there26 it would be noticeable27 but if a reduction should take place here28 it might not be noticed at all.29 Rab Judah stated: A careful study would show that30 according to the view of R. Meir roofs are regarded as a Separate domain, courtyards as a separate domain though it was bigger than two beth Se'ah. The sides of a ship that was inverted for the purpose of dwelling under it should be subject to the same laws as those of the walls of a dwelling-house. character as that of the top of a mere column; and when these sides are imagined to be extended upwards they surround an area that is bigger than two beth se'ah whose walls were not put up for dwelling purposes and whose status, therefore, must be that of a karmelith where movement of objects beyond four cubits is forbidden. domains from any of which it is forbidden to move objects into the other? domain, karpafs form a separate domain from which it is forbidden to move objects either into a courtyard or on to a roof. from which into a karpaf the movement of objects is forbidden.