How the Position Is Applied in a Modern City

A modern city is not classified by repeating what was true of a city several centuries ago. It is classified by applying the halachic definitions to the city's present physical form and public use.

That principle is especially important when discussing the position that "there is no reshus harabim today." In the Alter Rebbe's Shulchan Aruch, that statement rests on the authorities who require shishim ribo and on the factual situation in the places where the lenient minhag developed. If the facts change, the application has to be reconsidered.

Begin with the physical public domain

The Alter Rebbe's definition in 345:11 begins with streets and marketplaces sixteen amos wide. They must not be roofed. The status of surrounding walls and gates matters, as does the way a public road passes through an enclosed city. Intercity roads and roads connecting major public ways are also part of the discussion.

The requirement that a road in a walled city run from gate to gate is not the same as a general rule that every public street in every city must form one perfectly straight line across the entire municipality. The wording of 345:11 distinguishes a city enclosed by a wall from public roads without such an enclosing wall. Rabbi Levin cites a discussion of this distinction in the Tzemach Tzedek's chiddushim and develops its application in his study of city eruvin.

The full halachos of width, openness, mefulash streets and enclosure belong to the halachic definition of reshus harabim. They remain necessary even when the discussion turns to population and traffic.

Then ask whether shishim ribo is required

After the physical definition, the Alter Rebbe records the yesh omrim that require six hundred thousand people corresponding to the Midbar. The longstanding minhag he describes relied on that opinion.

A modern application therefore has two possible tracks.

According to the Rishonim and Poskim who do not require shishim ribo, the decisive questions are the physical character and public use of the way. A city cannot be removed from Torah-level reshus harabim merely because fewer than six hundred thousand people use it.

According to the authorities who do require shishim ribo, the number becomes an additional factual condition. A city in which the relevant public use does not reach that threshold may be treated as a karmelis on this ground, subject to the other halachos involved.

What exactly must reach six hundred thousand?

Even within the shishim ribo position, the modern calculation is not reduced to one universally agreed formula.

The Alter Rebbe's words in 345:11, ששים רבוא עוברים בו בכל יום, and his language in 363:42 can be read as focusing on the particular public area. Rabbi Levin openly acknowledges this reading before arguing against taking it to mean that six hundred thousand people must cross every individual street independently.

Earlier sources also speak of a city in which six hundred thousand are found or into which six hundred thousand regularly enter. In 392:1, the Alter Rebbe himself discusses the threshold while treating an entire city's eruv. Those formulations have led to broader readings based on the city or its public street system.

The practical consequence is simple. A modern traffic figure is meaningless until the halachic unit being counted has been defined. Daily entries into a city, daily users of its public street network, traffic on a major public corridor, and people crossing one fixed point are different measurements. One cannot select whichever number is convenient and call it "the 600,000 count."

The separate pages on City Population, Street Traffic, and Daily Passage and How Six Hundred Thousand Is Calculated address these readings in detail.

The Rebbe on changed factual conditions

The Rebbe addressed the underlying principle directly on Yud-Beis Tammuz 5745.

In the fourth sicha, the Rebbe was explaining that a halachic obligation may become practically applicable when circumstances change. As an example, he referred to the rule commonly stated in the past that there was no true reshus harabim because no city had the necessary six hundred thousand people. The Rebbe then described a case in which a count established that the city did in fact meet the threshold.

The Rebbe rejected the suggestion that the older statement should be treated as though it overrode the new facts. In the published free translation, his point is: "the reality can't be denied." What had not existed in the earlier factual setting could exist once the relevant reality changed.

The sicha does not require every large city to be declared a reshus harabim without analysis. It does not remove the disputes over how shishim ribo is measured, nor the other requirements of reshus harabim. It does rule out a different move: using the historical phrase "we have no reshus harabim" as proof that no later city can ever qualify.

The Rebbe's Yud-Beis Tammuz 5745 discussion gives the source in its broader setting.

A modern city requires current facts

A sound modern application therefore proceeds in order.

First, identify the public ways that may have the physical status of reshus harabim. Their width, openness, walls, gates and connections have to be understood under the relevant halachos.

Second, determine whether the halachic approach being applied requires shishim ribo. If it does not, a population or traffic number cannot by itself remove the Torah-level concern.

Third, if shishim ribo is required, define what is being counted before using a statistic. The dispute over street, area, city and public network has to be stated rather than hidden inside the number.

Fourth, use current measurements and current public-use facts. A statement written when no known local city met a threshold cannot establish that a city centuries later still fails it.

The factual application to New York and Brooklyn belongs on Shishim Ribo in New York City and Brooklyn and the separate Brooklyn and Reshus Harabim pages. The point here is the method. The older minhag is part of the halacha, but its factual premise has to be tested rather than assumed.