(Mishnah): If one is Noder Hana'ah (vows not to benefit) from seafarers, he may benefit from land dwellers; from land dwellers, he may not benefit from seafarers, since seafarers are included in land dwellers.

Not like these who go from Ako to Yafo, rather, to those who take extended voyages.

(Gemara): [The Seifa means] do not say that those who go from Ako to Yafo [are seafarers], rather, it is one who takes extended voyages.

[One who vows] from land dwellers, he may not benefit from seafarers. This is not only from those who go from Ako to Yafo, rather, [even] those who take extended voyages.

Question: Did he not vow from land dwellers?

Answer: This [is why our Mishnah] teaches that seafarers are included in land dwellers (for ultimately they dwell on the land).

If one vowed from seafarers [to take effect] after 30 days, and they became land dwellers, R. Yishmael and R. Akiva argue about this;

R. Yishmael says, the law depends on [the time that] the Neder [takes effect]. R. Akiva, it depends on [when she said] the Isur.

Those who go [on the sea] for excursion - this is a question [whether they are considered seafarers].

(Mishnah): If one vowed from 'Ro'ei ha'Chamah', he may not benefit even from blind people. He meant, those seen by the sun.

If one vowed from black-headed people, he may not benefit from bald people or white-haired people, but he may benefit from women and children. Only men are called black-headed.

If one vowed from Yeludim (those already born), he may benefit from Noladim (those who will be born).

[If one vowed] from Noladim - R. Meir permits even from Yeludim. (This cannot be understood simply, that he permits Noladim and even Yeludim! The Bavli says that the Mishnah is abbreviated. The full version is 'if one vowed from Noladim, he may not benefit from Yeludim. R. Meir says, even 'from Noladim', he may benefit from Yeludim, just like 'from Yeludim' may benefit from Noladim.)

Chachamim say, he intended only to those who enter the world through birth.

(Gemara) Question: What is R. Meir's reason?

Answer: "V'Atah Shnei Vanecha ha'Noladim Lecha" - they were already born.

Question: What is R. Meir's reason?

Answer: "Hinei Ven Nolad l'Veis David Yoshiyahu Shmo", and he was not born yet.