I am trying to understand the opinion of Rabbi Meir in the Mishna, Nedarim 9:3-4. If you are already familiar with Masekhet Nedarim, you can skip to the fourth paragraph of my question. If not, the following two paragraphs constitute an introduction to this issue:
The first of those two mishnayot concerns the nolad. This is a situation that was not present at the time the person made a vow, the presence of which would have caused him not to make it, but one which later becomes manifest. According to Rabbi Eliezer in Nedarim 9:2, we can annul a vow on the basis of a nolad. In one of the examples that he gives, if a person were to vow never to enter a particular building, and if that building were later to be made into a synagogue, the fact that he would not have made the vow had he known that it were going to become a synagogue means that (according to Rabbi Eliezer) the vow can be retroactively annulled. The sages disagree, since the building was not actually a synagogue at the time of the vow.
In mishna 9:3, Rabbi Meir declares that there are some things that are like a nolad without actually being a nolad at all. In the examples that he brings, it appears that the reason they are not really noladim lies in the fact that the one making the vow stipulates a reason explicitly; what makes them look like noladim is the fact that the reason later becomes untrue. By stipulating the reason, it is as though he is placing a condition on the vow, and since the condition is no longer existent the vow is invalid. For example, if he declares that he will not marry a certain woman because her father is wicked, and her father subsequently dies, Rabbi Meir permits his marrying the woman since his phrasing of the vow made the reason look like a condition that needed to be met for the vow to be in effect.
The phraseology of mishna 9:3 is such that it would suggest that Rabbi Meir agrees with the sages: one cannot annul a vow if the reason for its annulment is a [true] nolad. Where he disagrees with them here (if indeed he does; there are different girsaot) is in suggesting that this particular situation is permissible because it's not really a nolad; it merely looks like one.
Once we have established that Rabbi Meir agrees that one cannot retroactively annul a vow because of a nolad, how do we explain Nedarim 9:4? In this mishna, Rabbi Meir permits one to retroactively annul a vow that concerns a person's relationship with another Jew, by asking whether or not they would have made the vow if they had known that this other person might become poor and be unable to support himself without access to the vower's wealth. The wording is שמא יעני ואין אתה יכול לפרנסו; "perhaps he will become poor and you will be unable to support him". The man's response (אלו הייתי יודע שהוא כן לא הייתי נודר; "had I known that he [could become] this, I would not have vowed") is very similar to the wording used by Rabbi Eliezer in mishna 2 (אלו הייתי יודע שהוא נעשה בית הכנסת לא הייתי נודר; "had I known that it could become a synagogue, I would not have made the vow").
How is it possible to understand Rabbi Meir's opinion in Nedarim 9:4 as not concerning the annulment of a vow on the basis of a nolad (in this case, that the man might become poor)? And if it is impossible to do so, how is it possible to understand Rabbi Meir's opinion in Nedarim 9:3 as permitting such a thing?
