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Rabbi, greetings and blessings. Lately a number of questions have come up for me, and I would be glad if the Rabbi could share his opinion on them:

1. Kabbalah. Some time ago I asked the Rabbi what his opinion was about Kabbalah and what authority it has, and the Rabbi answered (as far as I remember) that these are spiritual intuitions, and someone to whom it “sounds”[1] right can/should act accordingly, while someone to whom it does not—should not. I wanted to ask whether the Rabbi still thinks what I remember, and if so, whether kabbalistic intuitions generally do sound right to the Rabbi, and whether he follows kabbalistic customs, or perhaps only partially—what yes and what no[2]?

Yes. I am speaking about kabbalistic ideas, not about customs. I do not think there is any necessary connection between the two. Where a kabbalistic custom entered Jewish law, it has a place. Otherwise I do not take it into account.

2. The Rabbi’s view on the question of “divine foreknowledge and free choice”: in the book Two Carts the Rabbi speaks near the end about the unity of opposites in connection with this question, and it sounds from there as though he definitely thinks this is a reasonable answer[3]. On the other hand, I seem to remember that in the book The Science of Freedom the Rabbi presents his view that it is entirely logical (and reasonable?) to say that the Holy One, blessed be He, does not know the future in full detail. If the possibility presented in The Science of Freedom is the correct one, the Rabbi wrote in Two Carts that we do not make statements about the Holy One, blessed be He, but only about the possibilities of our faith as human believers. I understood that this is connected to the fact that we do not know whether it is even possible to speak about logical limitations in relation to the Holy One, blessed be He, because we have no access to Him at all. Is that correct? And if so, how can one say that the Holy One, blessed be He, does not know the future in full detail[4]?

It absolutely does not represent my view. “The unity of opposites” is just empty verbiage. Such a statement has no meaning whatsoever, so I cannot agree or disagree with it. It’s like asking whether I agree with the claim that blah blah blah blah.
We most definitely know that there is no room for such talk. Since our whole discussion is about what we believe, there is no room for discourse outside logic even with respect to the Holy One, blessed be He. Maimonides wrote this in The Guide of the Perplexed, and Rashba wrote it in a responsum, among others (I cited this there).
It follows that if knowledge of the future is a logical contradiction, then it cannot be ascribed to the Holy One, blessed be He. In my book The Science of Freedom I explained why, in my opinion, this is a logical contradiction (as the Shelah wrote).

3. In the book The Science of Freedom, the Rabbi discussed the dualistic possibility that presents the creation of electrical circuits by a person’s will. Is there any way to detect the appearance of these circuits in a laboratory? (It could be that the Rabbi addressed this at the end of the book, and if so I apologize; the book just isn’t here with me in the yeshiva but at home…)

Theoretically yes. But practically it is difficult to hit exactly the point in space and time where this occurs.

4. In the Rabbi’s book The Science of Freedom, the Rabbi criticizes the view that understands the will as something that does not really exist on the level of particulars, but “emerges” in the whole. As an example he brings liquidity: although on the collective level one can speak about concepts like compressibility, viscosity, etc., which do not exist on the level of the individual particle, clearly they do not emerge out of nowhere, but simply describe the dynamics of a group of particulars, and that is why they do not apply to a single individual particle[5]. By contrast, in Two Carts, Gate 4 chapter 2, the Rabbi brings the example of a liquid as a concrete existence of a whole. It seems exactly the opposite?! Why does the critique from The Science of Freedom not apply here?

See in my book The Science of Freedom the distinction between weak and strong emergence. A public/collective is weak emergence, and that is possible.

5. Since we’re already on the subject of individual and collective, a question about this part in Two Carts[6]—why think at all (on the level of reasoning[7]) that there is such a thing as a “collective” in reality? After all, I can gather and disperse a group of people in an instant; am I really creating and destroying something in an instant? (Say I create a creative-writing group and then disband it. Was there really something here beyond a collection of people?)

Not every collection of people gathered in one place is a collective. Only a public—like the Jewish people. When you destroy the Jewish people, you have not destroyed only individuals but also the public as such. Likewise, when you replace all the cells in a body, it is still the same person (the Ship of Theseus). By the way, in the third notebook I discuss the idea that in order to turn a body into an organism, a soul is required—just as a king is needed for a people, and God for the world. Thus the heavenly prince of a given nation (in the language of the Sages, the angel of that nation) turns it into a people.

6. Absorption into utensils nowadays. I understand that there are several discussions on this topic, and the best known among them is the article in Techumin (by Dror Fixler, I think), and the question is what the Rabbi’s opinion is—does he think that for most utensils today, many of the ordinary laws of kashrut do not apply? Like Rabbi Dov Lior (from what I’ve heard), or that you can’t innovate new Jewish laws regarding utensils and the like, and we only have the categories known to the medieval authorities: earthenware, glass, and metal—like I heard Rabbi Yaakov Ariel said?

These are factual determinations, and there is no obstacle at all to innovating and changing accordingly.

7. Regarding changing a custom:

• I heard an interview of the Rabbi on the subject of kitniyot, but I didn’t hear it through to the end (my lunch break ended 🙂 ). Can one change a custom practiced by an ethnic community? I saw an article by some rabbi (I don’t remember his name) who wrote that there is no way to change a communal ethnic custom—not annulment of vows, nothing. Does the Rabbi agree? And if it is permitted to change, is annulment of vows needed? Does the one done before Rosh Hashanah help?

It is not a custom but a concern. See here:
https://mikyab.net/%D7%A2%D7%9C-%D7%92%D7%96%D7%99%D7%A8%D7%AA-%D7%A7%D7%98%D7%A0%D7%99%D7%95%D7%AA-%D7%A9%D7%9E%D7%A8%D7%A0%D7%95%D7%AA-%D7%95%D7%97%D7%99%D7%9C%D7%95%D7%9C-%D7%94%D7%A9%D7%9D-%D7%98%D7%95%D7%A8-2/

• Along the same lines—regarding changing the waiting period between meat and milk[8]: can one change the custom from waiting 3 hours to 1 hour? Is it simpler the other way around (from 1 hour to 3/6), or is it the same in the essential sense? Is annulment of vows needed? Is this similar to or different from kitniyot?

Annulment of vows is required, because this is a custom and not a concern. However, if the practice began because of a mistake (you thought it was law and it turned out not to be), then there is room to forgo annulment of vows.

• The text of Grace after Meals according to Rabbi Saadia Gaon. I saw people who recite Grace after Meals from the wording that appears in Rabbi Saadia Gaon’s prayer book (and it is much shorter). Is such a thing possible? And if we accepted upon ourselves (generally, in the later generations) a different wording—can that acceptance be changed[9]?

This is a custom, and annulment of vows is required.
That’s all for now, Rabbi,
Thanks in advance — Ofer Gazbar.
P.S. To finish, I’d like to ask a technical question: which regular classes does the Rabbi give during the week that it would be possible for me to attend?
[1] In the sense of “sounds right”…
[2] For example, does the Rabbi recite the entire text of the Blessing of the Moon, where I understood that the added section beyond the blessing itself is based on Kabbalah… does the Rabbi think it is “correct” to say three times “May terror and dread fall upon them,” etc…. or is that no longer connected to the kabbalistic intuitions that the Rabbi accepts?
[3] Or perhaps that is just an example of the unity of opposites and does not represent the Rabbi’s own view?
[4] Or perhaps this too is only a statement about the maximum our faith can say as human beings, while in truth it could be that the Holy One, blessed be He, does know the future in full detail?
[5] One has to take into account the field around each atom (is that relevant? I only remember that the Rabbi mentioned it, but maybe I’m mixing up a few points..). But in principle it is possible to calculate all the concepts that describe a whole, such as pressure, temperature, etc., even on the atomic level—if only we do enough work…
[6] Chapter 2 in Gate 4 — “The Centrality of the Individual.”
[7] On the level of proofs that Judaism relates to the collective as “existing,” I understand, but I don’t understand Judaism…
[8] Without addressing for the moment the question of whether it is appropriate or not…
[9] They said: why could Rabbi Saadia Gaon recite it that way and we cannot? Is the whole difference just some formal technicality (a general acceptance of a different wording) that needs to be annulled so that we too can recite it that way, or is there something substantively better about the wording we have?