Who is I L PERETZ who wrote the story If not higher?

You're likely thinking of I.L. Peretz, a prominent Yiddish writer. He is indeed the author of the short story "If Not Higher".

Here are some details about him:

* Full name: Yitzhak Leib Peretz (also sometimes transliterated as Itzik Leib Peretz)

* Dates: August 17, 1852 – August 8, 1915

* Nationality: Polish-Jewish

* Known for: He was a major figure in Yiddish literature, known for his short stories, plays, and poems.

* Themes in his work: He explored themes of Jewish life in Eastern Europe, the complexities of faith, and the struggles of social justice.

"If Not Higher" is a classic example of his work, often translated into English and other languages. It tells the story of a Jewish man who is forced to choose between his religious beliefs and his desire to help a stranger in need.