The Rambam on timtum halev

Summary: Did he really endorse the kabbalistic understanding of timtum halev?

Post: Towards the end of Shemini, we read:

43. You shall not make yourselves abominable with any creeping creature that creeps, and you shall not defile yourselves with them, that you should become unclean through them.

מג. אַל תְּשַׁקְּצוּ אֶת נַפְשֹׁתֵיכֶם בְּכָל הַשֶּׁרֶץ הַשֹּׁרֵץ וְלֹא תִטַּמְּאוּ בָּהֶם וְנִטְמֵתֶם בָּם:

44. For I am the Lord your God, and you shall sanctify yourselves and be holy, because I am holy, and you shall not defile yourselves through any creeping creature that crawls on the ground.

מד. כִּי אֲנִי ה אֱלֹהֵיכֶם וְהִתְקַדִּשְׁתֶּם וִהְיִיתֶם קְדֹשִׁים כִּי קָדוֹשׁ אָנִי וְלֹא תְטַמְּאוּ אֶת נַפְשֹׁתֵיכֶם בְּכָל הַשֶּׁרֶץ הָרֹמֵשׂ עַל הָאָרֶץ:

This is the basis for a rather famous derasha about timtum halev, on Yoma 39a:

תנא דבי רבי ישמעאל עבירה מטמטמת לבו של אדם שנאמר (ויקרא יא, מג) ולא תטמאו בהם ונטמתם בם אל תקרי ונטמאתם אלא ונטמטם

They taught in the academy of Rabbi Yishmael: a sin dulls {from the root טמם} the heart of man, as it states לֹא תִטַּמְּאוּ בָּהֶם וְנִטְמֵתֶם בָּם.

The basis of the derasha seems to be the krei vs. ketiv, leading to an al tikrei. That is, we should have expected an aleph in the word וְנִטְמֵאתֶם. Indeed, the Samaritans have that aleph. Since it is missing, the second ת is read as if it were a ט, and thus we have ונטמטם, 'and you will be dulled'.

Rashi explains there:
מטמטמת - אוטמת וסותמת מכל חכמה:

Now, there are two plausible readings of this gemara. One is that the gemara means specifically eating maachalos asuros, forbidden foods. After all, the prooftext is drawn from Shemini, where the peshat context was eating forbidden foods. Then, this is the basis of, or else is linked to, the (later) kabbalistic concept of timtum halev. And then, even accidental consumption of forbidden foods would have a deleterious spiritual effect on a person.

A second plausible reading is that the gemara is talking about any sin. After all, despite how it is often misquoted, the gemara actually says עבירה מטמטמת לבו של אדם, and aveira, not specifically eating a forbidden food. And the idea, perhaps from a rationalist perspective, is that acting in such a manner, deliberately, will have this negative effect on a person. He starts with one sin, thus making himself impure, and the consequence is this negative intellectual or spiritual effect. If so, it does not stand as the Talmudic basis or support for the kabbalistic idea, but is rather another example, which falls into a general pattern, of kabbalists retrojecting their ideas onto Chazal.

With this as background, I was surprised to see the following in Ateres HaMikra:

"Q: Is there an example how eating tereifos and neveilos has an impact on the soul of a talmid chacham?
 A: (The Gaon, Rav Chaim Soleveitchik of Brisk) (brought in the michtav yado of the Maggid of Ritteveh, HaGaon Rav Yissacher Ber {=a Rebbe, a student of the Chozeh of Lublin}:

"When the Rambam visited Yemen, he met a certain gaon of the geonim of the time. And after the Rambam returned home, this gaon would regularly write him questions and answers. One time, a letter reached him from the gaon, and on the page was a deep question in philosophy. The Rambam was much astounded at this question, and he said, 'I don't understand how this is so, that a question like this could arise in the mind of a Jew... for questions such as this do not arise in the Jewish mind until his soul is an impure soul. And the Rambam refrained from answering him regarding his question.

After some length of time, this fellow continued sending many letters, until the Rambam felt that he had to answer him. And his answer to the gaon was: Go and check the slaughterers and the inspectors in your community.

 Upon receipt of the letter, the gaon followed the instructions of the Rambam. And then was revealed that for thirteen years, they had fed him and the entire city neveilos and tereifos, such that even a gaon such as himself came up with a question of minus and apikorsus."

This story is just too perfect. Brought by a Rebbe, citing a scholar of Rambam, it presents the uber-rationalist Rambam endorsing, in a practical instance, the kabbalistic idea of timtum haleiv. Thus, it had an impact even though it was not consumed knowingly, and it was specifically maachalos asuros, as opposed to any sin.

There is the possibility of broken telephone at play here. Ideally, I would like to see this directly from  Rav Chaim Brisker (to see whether he said it, and if so if he was repeating a story he had heard or something he had seen directly), and more ideally, I would like to see this in an exchange from the Rambam and the gaon in Yemen directly. Otherwise, it is just too perfect a story, and seems apocryphal.

With some slight Googling, I see that this story is mentioned in a post at Havolim and discussed in this post at Rationalist Judaism about Tylenol and timtum halev.

From the Havolim post:

The sefer Mishuchan [sic] Gavo’ah here brings from the Ramban (discussed above) that the ma’acholim that the Torah assered were assered because they are bad for our health, and brings the Abravenel (discussed above) says that the Torah is not a medical book, and that these dinim are to protect our neshamos, not our bodies. He brings from the Magid from Ritteveh, Reb Yissochor Ber, that he heard from Reb Chayim Brisker that once the Torah made them assur, they are indeed mazik the body, as we see the din of timtum halev. He brings from the Brisker Rov that according to Reb Chaim, the timtum is only where al pi din the thing is assur to eat, but not for a choleh. He brings a story from the Briskers that the Rambam once visited Teiman, and met a great Gaon there, with whom he began a correspondence. Once he got a question from him that showed apikursus, and he refused to continue the correspondence. When the Teimani kept sending him inquiries, the Rambam told him to be bodeik the local kashrus. He later got a letter from the Gaon that he did investigate, and found that one local shochet had been ma’achil neveilos and treifos to the community for the past 13 years.

So there certainly is this tension here between an uber-rationalist reading of Rambam, and a more kabbalistic reading. It seems that Rav Chaim Brisker was harmonizing the two and brought the story as support.

In the comment section on Rationalist Judaism, Rabbi Natan Slifkin writes:

A "story from the Briskers" about Rambam which goes entirely against Maimonidean philosophy in several ways, does not have very much credibility.