Eruvin 76b — the Talmud in English

For

this applies—that with a circumference of three there is a width of one handbreadth—

when the shape is a circle—

in a circle.

But in a square, if you come to circumscribe the square with a circle, until you find within the circle a square whose length is four handbreadths on each side,

if one comes to circumscribe the square with a circle, until one finds within the circle a square whose side is four tefachim long,

we require a circumference

a circumference

more [according to Rashi, Sukkah 8a].

according to Rashi, Sukkah 8a].

And it entered our minds that it is sufficient for the circumference of the round window to be like the circumference of a four-by-four window [Meiri].

And therefore we wonder: In a square window of four by four, there is an inner circle whose width at its middle [diameter] is four handbreadths, like the width of the middle of the square.

And in order to draw this circle, it is necessary to multiply its diameter by three [as we say: anything whose circumference is three has a width of one handbreadth],

granted,

there is,

how much is the circumference of the

circle than the circumference of the inner

outer square

greater

than the circumference of

of

the inner circle

—

a quarter “from outside” [that is, an addition of one third to the circumference of the circle].

And since for a circle whose diameter is four we require twelve handbreadths, as we said, if you need to circumscribe the outer square—which is four by four—you must add one third to twelve, and

sixteen—

the circumference of a round window—

is sufficient, since with this circumference it was possible to circumscribe a four-by-four window. And see Tosafot, Sukkah 8a?! And we answer:

since with this circumference it would be possible to circumscribe a four-by-four window. See Tosafot, Sukkah 8a?! And we answered:

This applies—

when it is sufficient to add a quarter from outside—

a circle emerging from within

[that emerges from]

a square.

That is: if you come to calculate the circumference of the outer square from the circumference of an inner circle, and you know the circumference of the inner circle, you must add a quarter, and you have the circumference of the outer square.

But here this is not sufficient. Rather, we need the space of the window to contain a complete square of four by four surrounded by a circle, and not as we had assumed until now,

here this is not sufficient. Rather, we need a complete four-by-four square in the window’s opening, circumscribed by a circle, contrary to what we had assumed until now.

which is

a square emerging from within a circle, and you come to know the circumference of the outer circle when the datum in your possession is the circumference of the inner square [which in our case is sixteen handbreadths],

and one seeks to determine the circumference of the outer circle when the given measurement is the circumference of the inner square [in this case, sixteen handbreadths].

we require adding to it

that one add to it

more than a quarter.

than one quarter.

What is the reason?

Because of the projection of the corners [the addition of the diagonal of the square, which goes from corner to corner]. That is: the width of the circle wherever you measure it is as wide as the diagonal of the square. Whereas in the inner square, its width is not this width, except from one corner to another corner of the square; and therefore the circumference of the outer circle requires an addition greater than a quarter over the circumference of the inner square.

And we wonder: Ultimately, we do not require all this, for we need only multiply the length of the diagonal of the square—which is the width and diameter of the circle—by three, according to the calculation that “anything whose circumference is three has a width of one handbreadth.”

And let us examine:

Granted, every square cubit—

is a cubit and two fifths on the diagonal [every square cubit has a diagonal of one cubit and two fifths], and in a window of four by four, its diagonal is—according to this calculation—five cubits and three fifths.

If so, if the circumference of the round window is

And if so, if the circumference of the round window were

the

length of

seventeen less a fifth [seventeen cubits less five fifths] likewise

[seventeen cubits less one-fifth of a cubit],

is sufficient, since this is what results from tripling five cubits and three fifths; so why do I need twenty-four handbreadths?!

since that is the result of tripling five amot and three fifths. Why do I need twenty-four tefachim?!

And we answer:

Rabbi Yoḥanan—

the master of this statement concerning a round window—

said [held]

[held]

like the judges of Caesarea [the name of a place].

[the name of a place].

And some say, like the sages of Caesarea, who said:

A circle from within a square—

a quarter. The circumference of the inner circle within every square is smaller by a quarter than the outer square [as we said: by how much is the square greater than the circle? A quarter]. And

a square from within a circle—

half.

That is: the circumference of the inner square within the circle is smaller than the outer circle by half of the circumference of the inner square, namely by one third of the outer circle; it follows that the circumference of the square is two thirds of the circumference of the circle.

The reason is that every cubit in a square—according to their view—is two cubits on the diagonal [Tosafot]. It follows that in order to surround with a circle a square of one cubit by one cubit, you must triple two cubits, which is a circumference of six cubits. And since the circumference of the square is four cubits, you have two thirds of the circumference of the circle. And in order to surround a square window of four by four handbreadths, whose diagonal—according to this calculation—is eight handbreadths, you find a circle circumference of twenty-four handbreadths, and this is Rabbi Yoḥanan’s statement! And in the Gemara, Sukkah 8b, they said concerning the words of the judges of Caesarea, “It is not so, for we see that it is not so much” [for we see that it is not as much as they said].

We learned in the Mishna:

less than four by four,

or higher than ten, they make two and do not make one:

Rav Naḥman said: They taught

that we require the window to have part of it within ten handbreadths

only concerning a window between two courtyards.

But a window between two houses, even if

the window was

above ten

handbreadths from the ground of the house,

also, if they wished to make an eruv

together,

they make one.

What is the reason?

A house—

is considered as though filled. For since the house is roofed, it is considered full, and it is as though the window is not ten handbreadths high, since the entire house is filled [Mishna Berura; and see Gaon Yaakov. And see here the method of Rabbenu Yehonatan].

Rava raised an objection to Rav Naḥman

from what we learned in a beraita:

The same applies to me for a window between two courtyards,

and the same applies to me for a window between two houses.

And the same applies to me for a window between two upper stories,

and the same applies to me for a window between two roofs [for according to the Sages below, folio 89a, it is forbidden to take out from one person’s roof to another person’s roof until they make an eruv between them—Rashi. And see Gaon Yaakov concerning this].

And the same applies to me for a window between two rooms—in

in

all of them the window must be

these cases, the window

four

handbreadths

by four

handbreadths, and the window must be

within ten!

We see that even a window between two houses must be within ten. And this is difficult for Rav Naḥman?!

And we answer:

Interpret it—

establish what is stated in the beraita, that the window must be within ten, as referring to

a

window between two

courtyards only, and not to a window between two houses.

alone, and not to a window between two houses.

And we wonder: But it teaches,

“the same applies to me”! And this indicates that all of them are equal in their law.

which implies that all the cases have the same law.

And we answer:

Interpret it: the meaning of “the same applies to me” that it teaches, indicating that all of them are equal, is only with respect to the first law,

the meaning of “the same applies to me,” which indicates that all the cases are equal, applies only with regard to the first law,

a

window

four by four.

But not with respect to the second law, that the window must be within ten.

We establish that a ladder has the status of an “opening.” And if there is a ladder between two courtyards with a partition between them—if they wish, they make one eruv.

Rabbi Abba asked Rav Naḥman: A lul,

a round opening

opening from the house to the upper story,

and the house belonged to one person while the upper story belonged to another person, and they wish to make an eruv together—

do we say: Since the lul is higher than ten handbreadths from the ground of the house, they cannot make an eruv together through it [as with a window that is higher than ten, through which they do not make an eruv], but

it is necessary

to set up a

ladder

of steps,

fixed, in order

in place in order

to permit it

through the lul?

Or perhaps we say: A house is considered as though filled! Therefore the lul is not considered ten high, and they make an eruv between them through the lul,

perhaps we say: A house is considered as though it is filled. Therefore, the skylight is not considered ten high, and they may establish an eruv between them through the skylight,

and there is no need for a fixed ladder to permit it.

And Rabbi Abba explains his uncertainty: Is it that

when we say

“a house is considered as though filled”—

this applies concerning a window

with regard to a window

at the side

of the wall,

but in the middle,

at the height of the roof of the house,

not

do we say that there too the house is full?

Or perhaps -

it makes no difference

whether it is the side of the house from its middle?

He said to him

Rav Naḥman to Rabbi Abba:

it does not require

a ladder. For the house is considered as though it were filled, even with regard to an opening that is in the middle of the roof!

They understood from this:

specifically

a permanent ladder is what does not require

being there so that they could make an eruv through the way of the opening.

But a temporary ladder -

does require

that it be there.

But

it was stated:

Rav Yosef bar Minyומי said in the name of Rav Naḥman: Both a permanent ladder and a temporary ladder -

do not require one.

Mishna:

A wall between two courtyards, ten

handbreadths

high and four

handbreadths

wide -

the courtyards may make

two

eruvin, an eruv for each one,

but they may not make one

in order to carry from one to the other through the small holes between them.

If there were at its top

of this wall, which is four handbreadths wide,

fruits -

the people

these

in the one courtyard

go up from here and eat

on top of the wall.

And

the people

these

in the second courtyard

go up from here and eat.

See illustration

Provided that they do not lower

the fruits

down

below -

below, later, 92a.

For the wall is shared by both of them, and it is forbidden to take something out from a shared courtyard into the courtyard of an individual, [and this will be explained more fully in the Gemara].

But if the wall were less than four handbreadths wide and is not a domain in its own right, the Gemara nearby disputes what its law is.

(Was breached)

Was breached -

Rif, variant readings

the wall

between them, if the breach was

up to ten cubits

and ten is included, and the wall was not breached across its entire width of the courtyard,

they may make -

if they wish -

two

eruvin, and each one is permitted by itself, but they may not carry from one to the other.

And if they wish, they may make

an eruv

one

and they are permitted even to carry from one to the other.

And the reason that, if they wish, they may make two eruvin, and one courtyard does not prohibit the other is -

because it is

the breach between them

like an entrance.

For this is the measure of an entrance everywhere, and the courtyards are not breached into one another so that one should prohibit the other; rather, a partition - which has an entrance in it - separates them!

If the breach was

wider than this

than ten cubits, for a “breach” is in the partition separating them and not an “entrance” [and likewise if the courtyard was breached across its entire width, and no side-posts remained] - the inhabitants of the two courtyards become as though they all dwell in one courtyard [Rashi].

And therefore:

they may make one

and all may carry in both courtyards,

but they may not make two

even to permit carrying in each courtyard by itself, since this is like inhabitants of one courtyard who divided their eruv, and they accomplished nothing, and these prohibit those.

Gemara:

Introduction:

We learned later, 89a, and it was brought above, 74a:

Rabbi Shimon says: Both roofs, both courtyards, and both enclosures are one domain with regard to objects that had spent Shabbat in them, but not with regard to objects that had spent Shabbat inside the house.

It is permitted to carry from this person’s courtyard to that person’s courtyard objects that had spent Shabbat in the courtyard, because the courtyards are not considered divided domains on account of the change of ownership, so as to prohibit carrying from one courtyard to another as though these were two domains.

Only the houses themselves are considered divided domains, because they are a fixed dwelling place - Rashi, later, 91a.

But objects that had spent Shabbat inside the house and went out into the courtyard, even by way of permission - it is forbidden to carry them from one courtyard to another.

And we read later, 91a, and we also bring it above, 74a:

Rav said: The halakha is according to Rabbi Shimon [that the courtyards are one domain for objects that had spent Shabbat in them], and this is when they did not make an eruv [the inhabitants of one of the courtyards - Ritba].

But if they made an eruv, no [he may not carry from one to the other even objects that had spent Shabbat in the courtyard]. For we decree not to carry the courtyard’s objects, since it is common for objects that had spent Shabbat inside the house to be in the courtyard, having been brought out into the courtyard through the eruv that they made; and perhaps he will come to take objects of the houses out into the courtyard.

And Shmuel and Rabbi Yoḥanan disagree there, and ruled according to Rabbi Shimon, whether they made an eruv or whether they did not make an eruv. For in their view they did not decree concerning the courtyard’s objects even if the house’s objects are now commonly found in the courtyard.

And in the Gemara later, 92a, we prove from our anonymous Mishna, which teaches, “provided that they do not lower them down,” that it is forbidden to take from one courtyard to another even objects that had spent Shabbat in it [that is, the fruits], in a place where they made an eruv, and this is in accordance with Rav.

For necessarily, the reason that it is forbidden to lower the fruits from the wall into the courtyard [which is like from one courtyard to another] is because it is speaking of a case where they made an eruv, and taking from this one to that one was prohibited by decree, lest one bring up to the wall from the courtyard objects that had spent Shabbat in the house [Rabbeinu Yehonatan. And see there], and this is support for Rav.

And according to the one who does not decree, we reject it there: What is “below”? “Below, into the houses.” That is to say, in truth it is permitted from the wall to the courtyard, and we prohibit only bringing it into the houses.

If it does not have

in the wall between two courtyards a width of

four

handbreadths -

what

is its law regarding carrying from the courtyards onto it, and carrying on top of it?

Rav said: The airspace of the two

domains

that are on its two sides

governs it.

And therefore:

he may not move on it

fruits that had spent Shabbat on top of it,

even

as much as

the fullness of a hair

the thickness of a hair.

And Rashi explained: Since it is not significant enough to be a domain [for it does not have the measure of a domain that can stand in its own right], it is subordinate to both of them, and the domain of the two courtyards governs it, and they prohibit one another, and it is forbidden to carry even on its top.