According to many witnesses in Uruguay, Jorge Luis Borges was secretly learning with Professor Shoshani in Montevideo.
Here is a short story about that:
http://www.raoulwallenberg.net/wp-content/files_mf/6680.pdf
Levinas says in an interview:
“I am extremely grateful for what I learned from him [Shoshani]. In a haggadic text of the treatise 
Pirke Avoth, there is this phrase: “The words of the sages are like glowing embers.” One can ask, why embers, why not flame? Because it only becomes a flame when one knows how to blow on it! I have hardly learned to blow. There are always great minds who contest this manner of blowing. They say, “You see, he draws out of the text what is not in the text. He forces a meaning into it.” But if one does it with Goethe, with Valery, with Corneille, the critics accept it. It appears more scandalous to them when one does it with regard to Scripture. And one has to have met Shoshani in order not to be convinced by these critical minds. Shoshani taught me: what is essential is that the meaning found merits, by its wisdom, the research that reveals it. That the text had suggested it to you.”
In an interview of Elie Wiesel in 1978:
INTERVIEWER
What about Rav Mordechai Shushani? Where did you and he meet?
WIESEL
We met in Paris and I stayed with him for several years. He was a strange man. A genius who looked like a bum, or a clown. He pushed me to the abyss. But he believed in that. One day I am going to write a monograph about him. His concept was to shock, to shake you up, to push you further and further. If you don’t succeed, too bad. But you must risk it. If I had stayed with him longer, I don’t know what would have happened.
INTERVIEWER
Did he push anybody over the abyss?
WIESEL
He did. I heard stories later when I began picking up pieces looking for him. He did it with the best of intentions. Few people have had such an influence on my life as he did.
INTERVIEWER
Who were the others?
WIESEL
Here and there a teacher, a friend. But he is probably the strongest. He’s the opposite of Professor Saul Lieberman, who is no longer alive, but whom I considered to be the greatest Jewish scholar of his day. One cannot study the Talmud without the help of his commentaries. He was my friend and my teacher. Shushani, on the other hand, was not my friend. Surely he possessed a certain strength and power; so did Professor Lieberman—but his was not frightening.