In the context of Rabbi Hanina ben Gamliel’s position in the Mishna on yesterday’s daf that there is no need for a carefully crafted statement that delineates exactly what will happen in the event that a condition is fulfilled or left unfulfilled, the Mishna on our daf makes it clear that expectations still must be stated clearly in order for them to be considered seriously.
According to our Mishna, if a man says that he had certain expectations about the woman that he married (e.g. that she was from a family of kohanim or levi’im, or that she was wealthy) and that he now wants the marriage dissolved since he discovered that his assumptions were in error, we do not take his argument seriously, since she did not trick him. Some of the commentaries point out that by saying that “she did not trick him” the Mishna is implying that if she had misled him and had actually given him misinformation, then we might take his argument seriously and would consider annulling the marriage, since it took place under a mistaken impression.
The operating principle in this case is devarim she-ba-lev and the question is whether or not they are to be taken seriously.
The question of devarim she-ba-lev applies not only to marriage, but to other areas of halakha, as well. The apparent conclusion of our Gemara is that devarim she-ba-lev einam devarim – that we cannot consider unexpressed intentions. Rabbeinu Tam objects to this ruling based on the laws of korbanot (sacrifices) where we find that in a case where a person intends to declare a specific animal or object to be hekdesh (sanctified for use in the Temple), but inadvertently points to a different one, it is the intended one that become holy, not the one that was chosen accidentally. Rabbeinu Tam argues that this clearly shows that devarim she-ba-lev are taken into account by the halakha.
The Ramban responds by distinguishing between an accidental statement and a secret intent. The case where a person made a statement by accident would be considered an ones – something that happened that was beyond the person’s control – where we would not hold the person responsible. However, a person cannot simply come and claim that he had a secret intent that must be taken into account after the fact.
Most of the rishonim accept the approach of Rabbeinu Hananel who ruled that devarim she-ba-lev einam devarim, but that if circumstantial evidence points to the fact that the person meant to include a condition, it will be taken into account. Thus, for example, were someone to give away his estate, unaware that he would recover from his illness, we would recognize that his presents were made under mistaken assumptions and he could negate the gifts upon recovery.