There is a famous story of the Rambam in the name of R' Chaim Brisker:
"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."
What is the source of this story?
- Is it in any of R' Chaim's published works?
- Is it found in any Rishonim?