Divrei Torah:[1]
If one heard a [Torah] novelty, it is permitted to write it down in order so he does not forget it.[2] [The same applies if one came up on his own with a Torah novelty, that it is permitted to write it on Chol Hamoed in order so he does not forget the subject.[3] It is permitted to even initially study Torah during the Moed with intent of novelizing Torah thoughts and then writing it down.[4] There were Gedolei Yisrael who continued writing their Torah novelties on Chol Hamoed.[5] The Torah novelties are to be written in regular script “Meshita” and not in boxed script used for Stam.[6]]
Copying a Sefer:[7] If one happened upon a new Sefer during the Moed, it is permitted to write a copy of it [in order so he does not forget the information[8]] if he will be unable to do so after the Moed.[9] [It goes without saying that one may photo copy it by machine.]
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[1] Michaber 545:9; Hagahos Semak based on Temura 14b
[2] The reason: As the Sages did not decree against writing down Torah in a case that one may come to forget it, as even in times that writing the oral Torah was forbidden, it was permitted to write Torah novella. [See Michaber ibid, Hagahos Semak ibid, Taz 545:13] Alternatively, the reason is because if one forgets the Torah novelty, or if he is required to restudy it after the Moed in exchange for moving on to other subjects, it is considered a Davar Haved, which is permitted to be performed during Chol Hamoed. [Taz 545:13; See P”M 545 M”Z 13 who understands this to be the main reason of the allowance]
[3] M”A 545:26
[4] Taz 545:13
The reason: As one is constantly obligated to learn and novelize Torah, and if we require him to delay this until after the Moed, he will need to replace his time after the Moed for this learning in exchange for learning what he had scheduled, and there is no greater “Davar Haveid” of Torah learning time than this. [Taz ibid]
[5] Taz ibid that so did Bach
[6] Taz ibid
[7] Michaber ibid; Semak ibid
[8] M”A 545:26
