Bava Batra — Daf 41a

סתמא מאי רבינא אמר לא חיישינן רב אשי אמר חיישינן והלכתא חיישינן:

מתני׳ כל חזקה שאין עמה טענה אינה חזקה כיצד אמר לו מה אתה עושה בתוך שלי והוא אמר לו שלא אמר לי אדם דבר מעולם אינה חזקה

שמכרת לי שנתת לי במתנה אביך מכרה לי אביך נתנה לי במתנה הרי זו חזקה והבא משום ירושה אינו צריך טענה:

גמ׳ פשיטא

מהו דתימא האי גברא מיזבן זבנה ליה האי ארעא ושטרא הוה ליה ואירכס והאי דקאמר הכי סבר אי אמינא מיזבן זבנה לי האי ארעא אמרי לי אחוי שטרך הלכך לימא ליה אנן דלמא שטרא הוה לך ואירכס כגון זה (משלי לא, ח) פתח פיך לאלם הוא קמ"ל

(ענ"ב סימן)

רב ענן שקל בידקא בארעיה אזל הדר גודא בארעיה דחבריה אתא לקמיה דרב נחמן א"ל זיל הדר

והא אחזיקי לי אמר ליה כמאן כר' יהודה ור' ישמעאל דאמרי כל בפניו לאלתר הוי חזקה לית הלכתא כוותייהו

אמר ליה והא אחיל דאתא וסייע בגודא בהדאי אמר ליה מחילה בטעות היא את גופך אי הוה ידעת לא עבדת כי היכי דאת לא הוה ידעת הוא נמי לא הוה ידע

רב כהנא שקל בידקא בארעיה אזל הדר גודא בארעא דלא דידיה

What is the rule where the donor does not specify [the place of writing]?  — Rabina said that we take no account of this;  R. Ashi said that we do take account of it.  The law is that we do take account of it. MISHNAH. THE FACT OF POSSESSION  IF NOT REINFORCED BY SOME PLEA OF RIGHT DOES NOT OF ITSELF CONFER A TITLE OF OWNERSHIP. FOR INSTANCE, IF A MAN SAYS TO ANOTHER, WHAT ARE YOU DOING ON MY PROPERTY, AND HE REPLIES, NO-ONE HAS EVER SAID A WORD TO ME ABOUT IT, HIS OCCUPATION CONFERS NO TITLE. IF, HOWEVER, HE PLEADS, I AM HERE BECAUSE YOU SOLD THE LAND TO ME, BECAUSE YOU GAVE IT TO ME, BECAUSE YOUR FATHER SOLD IT TO ME, BECAUSE YOUR FATHER GAVE IT TO ME, THEN HIS OCCUPATION CONFERS A TITLE OF OWNERSHIP. AN OCCUPIER BY VIRTUE OF INHERITANCE  DOES NOT REQUIRE ANY SUCH PLEA. GEMARA. [THE FACT OF POSSESSION IF NOT REINFORCED BY SOME PLEA OF RIGHT DOES NOT OF ITSELF CONFER A TITLE OF OWNERSHIP.] Surely this is self-evident? — [The reason for stating it is this] We might say: The land really was sold to this man, and he had a deed and has lost it, and the reason why he pleads as he does is because he thinks that if he says he bought the land he will be asked to produce the deed of sale. Let the Beth din then suggest to him that perhaps he had a deed and lost it, on the principle of Open thy mouth for the dumb.  The Mishnah therefore tells us [that this is not so]. (Mnemonic 'ANaB.) R.'Anan's  field was flooded through the bursting of a dam.  He afterwards went and restored the fence, [which, however, he built] on land belonging to his neighbour. The latter [on discovering this] sued him before R. Nahman. He said to him: 'You must restore the land.' 'But,' he rejoined, 'I have become the owner of it by occupation?'  — Said R. Nahman to him: 'On whose authority [do you rely]? On that of R. Ishmael and R. Judah, who both lay down that [if the occupation takes place] in presence of the owner [without protest], it constitutes a title at once. The law however, is not in accordance with their ruling.'  R. 'Anan thereupon said: 'But this man has tacitly waived his right because he came and helped me to build the fence?' R. Nahman replied: 'This was a waiver given in error. You yourself, had you known that the land was his, would not have built the fence on it. Just as you did not know, so he also did not know.' R. Kahana's land was flooded through the bursting of a dam. He afterwards went and built a new fence on land which did not belong to him.