Hászágát gvul / Gemárá, risonim

§ Rav Huna said: There was a certain resident of an alleyway who set up a mill in the alleyway and earned his living grinding grain for people. And subsequently another resident of the alleyway came and set up a mill next to his. The halakha is that the first one may prevent him from doing so if he wishes, as he can say to him: You are disrupting my livelihood by taking my customers.

The Gemara suggests: Let us say that a baraitasupports his opinion: One must distance fish traps from fish, i.e., from other fish traps, as far as the fish travels, i.e., the distance from which the fish will travel. The Gemara asks: And how much is this distance? Rabba bar Rav Huna says: Up to a parasang [parsa]. This indicates that one must distance himself from the place where another has established his business. The Gemara responds that this is no proof: Perhaps fish are different, as they look around. One fish explores the area ahead of the others, indicating to them where to go. Once they encounter the first trap they will not approach the second.

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מרחיקין מצודת הדג כולי‎—We distance the fish nets, etc.

OVERVIEW
The גמרא cites a ברייתא which states that one must distance his trap to catch fish from an existing trap, the distance that a fish can travel (which is a פרסה). This proves that one cannot encroach on his fellow’s livelihood. תוספות discusses this ruling.
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תוספות anticipates a difficulty:
אף על גב דרבינו תם מפרש דבדבר של הפקר אפילו רשע לא מיקרי –
Even though that the ר"ת explained that by an item of הפקר, one is not even called a רשע if he encroaches on his friend’s intent to acquire the הפקר item. The ר"ת proves this –
כדתנן (פאה פרק ד משנה ג) גבי פאה פירס טליתו עליה מעבירין אותו ממנה‎ –
As the משנה taught regarding פאה, ‘if a poor person spread out his טלית over the פאה (with the intent of acquiring it for himself), the rule is we remove him from this פאה and we allow the other poor people (also) to collect the פאה‎ –
Another proof to the view of the ר"ת:
וכן תנן בפרק קמא דבבא מציעא (דף י,א) ראה את המציאה ונפל עליה ובא אחר והחזיק בה‎ –
And similarly the משנה taught in the first פרק of מסכת ב"מ, ‘he saw a מציאה and fell on it (but did not pick it up) and another person came and took possession of it, the rule is –
זה שהחזיק בה זכה‎ –
The one who took possession acquires it’, and we do not consider him to be a רשע even though his friend wanted it and made his intention clear by falling on the מציאה‎ –
ולא מיקרי רשע אלא בעני המהפך בחררה ובא אחר ונטלה‎ –
And one is not called a רשע in these cases of הפקר, only by a case of עני המהפך בחררה and another came and took it away from the עני, in that case he is called a רשע‎ –
משום שאם לא ישתכר במקום זה ימצא להשתכר במקום אחר‎ –
Because we say to him that if he will not profit in this place, he will find another place from where to profit –
תוספות now answers his initial question:
והך דשמעתא לא קשיא דאף על גב דהוי דבר של הפקר‎ –
And there is no difficulty from this ruling here, even though the fish is an item of הפקר, and by הפקר there is no rule of עני המהפך בחררה, it is free for anyone –
מכל מקום בכמה מקומות ימצא שיוכל לפרוס מצודתו ועוד דהכא אומנותו בכך‎ –
Nevertheless, he can find many other places where he can spread his net, and additionally that here this is his trade and livelihood of the initial fisherman –
תוספות continues with a question:
והא דאמרינן בפרק חזקת הבתים (לקמן דף נד,ב) נכסי כנענים הרי הן כמדבר‎ –
And this which רב יהודה אמר שמואל states in פרק חזקת הבתים; ‘the properties of gentiles, which are being sold to Jews, are like a wilderness; meaning they are הפקר, so that –
כל המחזיק בהן זכה בהן מאי טעמא‎ –
Whoever takes possession of them acquires them’; the גמרא explains, that the reason is –
כנעני מכי מטא זוזי לידיה איסתלק ליה וישראל לא קני עד דמטי שטרא לידיה‎ –
As soon as the gentile receives the money in his hand, he is removed from the property, and the ישראל who is purchasing the land does not acquire it until he receives a deed in his hand –
ופירש רבינו שמואל בן מאיר התם דישראל המחזיק רשע מיהא מיקרי –
And the רשב"ם explained there that the other ישראל (not the purchaser) who takes possession of the property, is nevertheless called a רשע‎ –
ולפירוש רבינו תם אפילו רשע לא הוי כיון שלא ימצא במקום אחר –
However according to the פירוש ר"ת the מחזיק is not even considered a רשע, since he cannot find a הפקר property elsewhere –
וקשה לרבינו שמשון בן אברהם מהא דאמר באיזהו נשך (בבא מציעא דף עג,ב) –
So based on the aforementioned, the רשב"א has a difficulty with the פר"ת from this which the גמרא states in פרק איזהו נשך‎ –
רב מרי בר רחל משכן ליה ההוא נכרי ביתא אזל רבא וזבניה‎ –
A certain gentile transferred his house to רב מרי בר רחל as a security (משכון) for a loan; רבא went and bought this house from the נכרי, while רמב"ר was still living in the house –
נטר תריסר ירחי שתא שקל אגר ביתא אמטייה לרבא –
רמב"ר waited twelve months and then took with him the rent for the house and bought it to רבא‎ –
אמר ליה האי דלא מטאי לה למר אגר ביתא עד השתא דאמר מר סתם משכנתא שתא‎ –
רמב"ר said to רבא, ‘the reason that I did not bring you rent until now (for the past twelve months) is because the master said that an unqualified משכון is for one year –
ולא מצי נכרי לסלוקי –
And the נכרי cannot remove me for this whole year’. This concludes the גמרא‎.
והשתא כיון שקדמה חזקת רב מרי לחזקת רבא –
But now since the חזקה of ר"מ preceded the חזקה of רבא‎ –
אם כן זכה בה רב מרי דנכסי הכנעני הרי הן כמדבר‎ –
Therefore ר"מ acquired the house, since we said that the properties of a נכרי who is selling to a ישראל are הפקר like a מדבר‎. The question therefore is why did רמב"ר need to pay rent to רבא, since the house now belonged to רמב"ר.
ואי מקרי רשע אתי שפיר דלא היה רוצה לזכות בה‎ –
So if he is called a רשע (as the רשב"ם stated), it is understood why ר"מ paid the rent, since he did not want to acquire it (for he did not want to be a רשע) –
אבל לפירוש רבינו תם דאפילו רשע לא מיקרי‎ –
However according to the ר"ת that רמב"ר would not even be called a רשע‎ –
אמאי לא זכה בה רב מרי כיון דהיתר גמור הוא‎ –
Why did not ר"מ acquire it, since it is perfectly permissible?!
תוספות responds:
ושמא לפנים משורת הדין עבד‎ –
And perhaps רמב"ר acted beyond the requirement of the law; he did not want to cause a loss for רבא, even though legally it is permitted.
תוספות offers an alternate explanation:
ולרבינו יצחק בן אברהם נראה דחזקת רב מרי לא היתה אלא בתורת משכון –
And it appears to the ריב"א that ר"מ took possession only in regards to a משכון, but he had no intention of making a חזקה for ownership –
ורבא קנה ממנו בשטר וזכה בה ואחר כך נתן מעות
And (additionally/alternately) רבא bought the house from the נכרי with a שטר and thereby acquired it first and only afterwards did he give the money to the נכרי‎.
[ועיין עוד תוספות קדושין נט,א דיבור המתחיל עני המהפך וכולי ותוספות בבא מציעא עג,ב: סוף דיבור המתחיל נטר]:

SUMMARY
The ruling of עני המהפך בחררה does not apply to הפקר, except for cases like fishing (where there are other places to fish) or where one is encroaching on someone’s livelihood. A חזקה for a משכון is not effective for an ownership חזקה‎.

THINKING IT OVER
From תוספות it seems that רבא acquired the house with the receiving of the שטר‎. However תוספות there in ב"ב (נד,ב ד"ה עובד) clearly states,שטר ודאי לא קנה בעובד כוכבים, so תוספות should have rather answered that רבא gave him the money at the same time that he received the שטר‎.

The Gemara further relates: Rav Giddel was engaging in the acquisition of a certain plot of land. In the meantime Rabbi Abba went and purchased it. Rav Giddel went and complained about Rabbi Abba to Rabbi Zeira. Rabbi Zeira went and complained about Rabbi Abba to Rav Yitzḥak Nappaḥa. Rav Yitzḥak Nappaḥa said to him: Wait until Rabbi Abba ascends to visit us for the pilgrimage Festival, when all come to hear the Festival sermon, on which occasion we can discuss this matter with him. When Rabbi Abba ascended Rav Yitzḥak Nappaḥa found him and said to him: If a pauper is engaging in the acquisition of a loaf of bread that he found, and another came and took it from him, what is the halakha?

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Ravina said to Rava: Shall we say that Rav Huna spoke in accordance with the opinion of Rabbi Yehuda? As we learned in a mishna (Bava Metzia 60a): Rabbi Yehuda says: A storekeeper may not hand out toasted grain and nuts to children who patronize his store, due to the fact that he thereby accustoms them to come to him at the expense of competing storekeepers. And the Rabbis permit doing so. This indicates that according to the opinion of Rabbi Yehuda, all forms of competition are prohibited, which would include the scenario concerning the mill.