Bava Batra

[For] he  was in doubt as to whether the halachah is in accordance [with the decision of] Rabbi [when it is in opposition to that] of his colleague,  but not [when it is opposed to that] of his colleagues,  or is the halachah in accordance [with] Rabbi [when in opposition to] his colleague and even [when he is opposed to] his colleagues. R. Nahman said in the name of Rab, 'It is forbidden to act in accordance with the decision of Rabbi,  for he holds the opinion [that] the halachah is in accordance [with] Rabbi, [when in opposition to] his colleague, but not [when he is opposed to] his colleagues.' R. Nahman in his own name,  however, said, 'It is permitted to act in accordance with the decision of Rabbi'; for he holds the opinion [that] the halachah is in accordance [with] Rabbi [when in opposition to] his colleague and even [when opposed to] his colleagues. Raba said, 'It is forbidden to act in accordance with the decision of Rabbi, but if one did act [accordingly], his action is legally valid;'  for he is of the opinion [that at the college] it was said [that they were only] inclined  [in favour of the opinion of the Rabbis]. R. Nahman learned  in the 'other books of the School of Rab':  Of all that he hath,  excludes the appreciation [of an estate] which the heirs have produced after the death of their father; but [in] the [natural] appreciation of the estate [that accrued] after the death of their father he [does] take [a double portion]. And who is [the author of this statement]? — It is Rabbi. Rami b. Hama learned in the 'other books of the School of Rab':  Of all that he hath,  excludes  the [natural] appreciation of an estate [that accrued] after the death of their father, and much less is he [entitled] to take [a double portion in] the appreciation which the heirs produced after the death of their father. And who is [the author of this statement]? — The Rabbis. Rab Judah said in the name of Samuel: A firstborn son does not take a double portion in a loan.  [According] to whom [was this statement required]?  If it is suggested, [according] to the Rabbis, [it may be retorted] if the Rabbis maintain that an appreciation which accrues to his possession  [the firstborn] takes no [double portion], is there any need [to state that he takes no double portion in] a loan?  — But [the statement was required according] to Rabbi. Who, then, was the author of] what has been taught. 'If they inherited a bond of indebtedness, the firstborn takes a double portion both in the loan and in the interest'? Neither Rabbi nor the Rabbis!  This statement  may, indeed, be required [according] to [the view of] the Rabbis,  [for] it might have been assumed [that, in the matter of] a loan, since he is in possession  of the bond, [the debt] is regarded as collected, hence [the law] had to be stated. [A message] was sent from Palestine:  a firstborn takes a double portion in a loan, but not in [its] interest.  [According] to whom [is this law]?  If it is suggested [that it is according] to the Rabbis, [it may be retorted:] If the Rabbis maintain that [in] an appreciation which accrues to his possession [the firstborn is] not to take [a double portion], is there any question as to [whether he takes a double portion in] a loan?  — But [the statement is according] to Rabbi. [Does] not [the firstborn, however, according] to Rabbi [take a double portion] in the interest [also]? Surely it was taught: Rabbi said: A firstborn takes a double portion both in a loan and in [its] interest! — This is really [in accordance with] the Rabbis, but a loan [is regarded] as collected. R. Aha b. Rab said to Rabina: Amemar [once] happened to come to our place, and gave the following exposition: A firstborn takes a double portion in a loan but not in [its] interest. He said to him: The [scholars] of Nehardea follow their [own] view;  for R. Nahman said:  [If] land was collected [for the debt, the firstborn] has no [double portion],  [if] money was collected he has [it],  but Rabbah said: [If] money was collected he has no [double portion],  [if] land was collected, he has. Abaye said to Rabbah: Following  you there is a difficulty; following  R. Nahman there is a difficulty. Following you there is [this] difficulty: