"man seduces a woman for the sake of marriage"

Question

Rambam isurai bia 21:13 (Chabad , sefaria , Hebrewbooks , mechon-mamre)

Whenever...a man seduces a woman for the sake of marriage...all of the children born in these situations will be rebellious and sinful. (Chabad translation)

Is this true that that a man should not seduce a woman for the sake of marriage?

1. Are there groups of Jews careful with this?
2. Do later rabbis bring this law?
3. What is the source of this law?
4. What is the definition of seduce in this case does it include persuasion (warning YouTube link)?
   If not, is persuasion permitted/preferred/ avoided?

Sources on subject will be greatly appreciated

Answer 1

The Gemara gives a different list, and it didn't have בני מפותה. This is the same list as דרכי טהרה from Harav Eliyahu zt"l who omits בני מפותה. I would assume that the Rambam is talking about the "seducing" in the Torah where she is a minor. It doesn't make sense to say that courtship is illegal.

The list from the Gemara are as follows:א) בני אנוסה. ב) בני שנואה. ג) בני נידוי. ד) בני תמורה. ה) בני מורדת. ו) בני שכרות. ז) בני גרושת הלב. ח) בני ערבוביה. ט) בני חצופה. י) ויש אומרים אף בני ישנה.

Translation: 1) forced (meaning spousal rape) 2) hated (husband hates his wife; even if he is just mad, he needs to make up first) 3) excommunicated (he declares that he will not receive benefit from his wife) 4) he has two wives and thinks of his other wife 5) when the wife is angry with her husband 6) drunk 7) has in mind to divorce her 8) thinks of a totally different woman 9) when she actually asks with words instead of hinting 10) some say while she is asleep

Answer 2

@mevaqesh brought a few sources on the subject

Rav Shmaryahu Yosef Chaim Kanievsky brings the sources of this part of the Rambam's halacha in his book Kiryas Melech:
Mesehta Kala Rabisi chapter 1

ברייתא מכאן אמרו עשרה כממזרים ואינם ממזרים ... בני מפותה
...גמ'] בני מפותה סופן שמפתין לבן
~:
part of the list of 10 who are similar to mamzerim, are the sons of a seduced woman, the gemorah explains what will happen to them is that they will be seduced by a boy (man)

the list of the "10 mamzerim" is also brought in Pirkei Rabbeinu HaKadosh 10:3

and in mishnas Rabbi Elazar 18 in the list of the children of the nine midos (which is different then the list in the Shulchan Arch 240.3
but there sons of a seduced woman are defined as: when a man has relations with his engaged (kedushin) wife to be while she was still in her father's house and without a kesuba.

---

this Rambam is also brought by the Ungvarer Rebbe Menashe Klein (about him in hebrew (chabad)) in the book Mishneh Halachos part 12:301 (text version) in his answer about ~ "what is the problem with walking with a girl and talking to her to check if she is good for him to marry"
where he brings this Rambam and proves that the "seducing" in this Halacha does not mean that the man had relations with her but only that he convinced the girl to marry him.
it seems his option on Jewish dating is that
1. the man can look on the girl if he wants to check if she is disgusting to him, once he checked he can not look again, 2. it is good if the girl is shy from the man like Rivka did when she fell of the camel (http://www.sefaria.org/Genesis.24.64),
3. no convincing of the girl is permitted, only we ask her if she wants as they did by Rivka (http://www.sefaria.org/Genesis.24.57)
and not (the nonjewish way), as shechem did to Dina (Rashi Beraishis 34.3)