Our Gemara quotes a Mishna that teaches that if an abandoned child is found, the halakha treats him differently depending on the population of the city:
- If the majority of the city’s population is non-Jews, the child is considered a non-Jew.
- If the majority is Jewish, the child is considered Jewish.
- If there are an equal number of Jews and non-Jews, the child is considered Jewish.
What is unclear is what areas of halakha this applies to. Both Rav and Shmuel agree that these rules do not apply to the questions of yikhus – of family pedigree – but to other halakhot. Rav, for example, says that the rules apply to the question of le-hahayoto (to sustain him). Although this term could be understood to mean whether the community is obligated to save the child from a dangerous situation, the rishonim understand it to mean that the question is whether the Jewish community is obligated to raise and support this child. According to this approach, Rav is teaching that even situations that are not life-or-death must be taken seriously by the Jewish courts with regard to this child.
One issue raised by the rishonim is why we do not simply convert the child, which would solve all of these problems; in any case he will be raised in the Jewish community and be supported by them? Several explanations are given in response. First of all, we have already learned (on daf 11) that according to most opinions, a Jewish court will only agree to convert a child if he is brought by his parents or requests the conversion on his own; the beit din will not take such an initiative on its own. Furthermore, we have learned that upon reaching maturity a child who converts is given the opportunity to reject the conversion that was done, which will effectively remove any advantage that the conversion would have given us.