Bava Metzia — Daf 3b

והאי בכוליה בעי דלודי ליה והאי דלא אודי אשתמוטי הוא דקא מישתמט מיניה סבר עד דהוו לי זוזי ופרענא ליה ואמר רחמנא רמי שבועה עליה כי היכי דלודי ליה בכוליה

אבל העדאת עדים דליכא למימר הכי אימא לא קמ"ל ק"ו

ומאי ק"ו ומה פיו שאין מחייבו ממון מחייבו שבועה עדים שמחייבין אותו ממון אינו דין שמחייבין אותו שבועה

ופיו אין מחייבו ממון והא הודאת בעל דין כמאה עדים דמי

מאי ממון קנס ומה פיו שאין מחייבו קנס מחייבו שבועה עדים שמחייבין אותו קנס אינו דין שמחייבין אותו שבועה

מה לפיו שכן מחייבו קרבן תאמר בעדים שאין מחייבין אותו קרבן

הא לא קשיא רבי חייא כרבי מאיר סבירא ליה דאמר עדים מחייבין אותו קרבן מק"ו

דתנן אמרו לו שנים אכלת חלב והוא אומר לא אכלתי רבי מאיר מחייב וחכמים פוטרים

אמר רבי מאיר אם הביאוהו שנים לידי מיתה חמורה לא יביאוהו לידי קרבן הקל אמרו לו מה אם ירצה לומר מזיד הייתי יפטר

אלא מה לפיו שכן מחייבו אשם אשם היינו קרבן

אלא מה לפיו שכן מחייבו חומש הא לא קשיא רבי חייא כרבי מאיר סבירא ליה כי היכי דמחייב ליה קרבן מק"ו מחייב ליה חומש מקל וחומר

אלא מה לפיו שכן אינו בהכחשה ובהזמה תאמר בעדים שישנן בהכחשה ובהזמה

אלא אתיא מעד אחד ומה עד אחד שאין מחייבו ממון מחייבו שבועה עדים שמחייבין אותו ממון אינו דין שמחייבין אותו שבועה

מה לעד אחד שכן על מה שהוא מעיד הוא נשבע

On the other hand, it may be assumed that the defendant would have been ready to admit the whole claim,  and that he has not done so because of a desire to put the claimant off for a time, thinking: 'When I shall have money, I shall pay him.' Therefore the Divine Law imposes an oath upon him, so that he may admit the whole claim. But as regards the testimony of witnesses, where this argument does not apply,  I should have thought that no oath ought to be imposed. Therefore it is necessary to prove by a Kal wa-homer that in this case also an oath is to be imposed. And what is the Kal wa-homer? — [It is as follows:] If [the words of] his own mouth,  which do not oblige him to pay money, make it necessary for him to take an oath, how much more ought the evidence of witnesses, which obliges him to pay money, make it necessary for him to take an oath? But is it right to say that [the words of] his own mouth do not oblige him to pay money — in view of [the established principle] that the admission of a defendant is equal to the testimony of a hundred witnesses? — What is meant by the payment of money is the payment of a fine.  [And the Kal wa-homer is as follows:] If [the words of] his own mouth, which do not oblige him to pay a fine, make it necessary for him to take an oath, how much more ought the evidence of witnesses, which obliges him to pay a fine, make it necessary for him to take an oath? [But then it could be argued:] Does not a person's own mouth carry more weight [than the evidence of witnesses] in that it can oblige him to bring an offering,  while the evidence of witnesses does not oblige him to bring an offering?  — This objection is not valid: R. Hiyya is of the same opinion as R. Meir, who says that witnesses do make it necessary for the offender to bring an offering, [and he infers it] by means of a Kal wa-homer. For we learnt:  When two persons say to a third person: 'You have eaten forbidden fat [unawares]', but he says: 'I have not eaten any'. R. Meir maintains that he is obliged to bring an offering, but the Sages  declare him free. R. Meir argues: If two [witnesses] can bring upon an offender such a severe penalty as death, should they not be able to bring upon him the light penalty of an offering? To this the Sages oppose the argument: Had he desired [to prevaricate] he could have said, 'I did it deliberately', and he would have been free [from bringing an offering]. But [the argument continues]: Does not a person's own mouth carry more weight [than witnesses] in that it can oblige him [in a case of confession after denial on oath] to bring a guilt-offering?  But [it is immediately objected]: A guilt-offering is also an offering [and this argument has already been dealt with]! — Then [put it this way]: Does not a person's own mouth [in a case of confession after a denial on oath] carry more weight than witnesses, in that it can oblige him to pay a 'fifth'?  — This objection is not valid: R. Hiyya is of the same opinion as R. Meir, who says that just as witnesses oblige the offender to bring an offering — because of the Kal wa-homer inference — they also oblige him on the same ground to bring a 'fifth'. But [it can still be objected]: Does not a person's own mouth [in the case of the admission of a debt] carry more weight [than the evidence of witnesses] in that it cannot be refuted by a denial or an alibi proof  on the part of witnesses, while the evidence of witnesses can be refuted by a denial or an alibi proof on the part of other witnesses? — [The Kal wa-homer must] therefore be derived from 'one witness': If one witness, whose evidence does not oblige a defendant to pay money, obliges him to take an oath,  how much more should several witnesses, whose evidence does oblige a defendant to pay money, oblige him to take an oath. But [it can be objected]: The oath that is imposed by the evidence of one witness refers only to the part of the debt to which the witness testifies [and which the defendant denies],