Israel Shahak (Hebrew: ישראל שחק‎; born Himmelstaub, April 28, 1933 – July 2, 2001) was a Polish-born Israeli professor of chemistry at the Hebrew University of Jerusalem, known especially as a radical political thinker, author, and civil rights activist. Between 1970-1990, he was president of the Israeli League for Human and Civil Rights and was an outspoken critic of the Israeli government. Shahak's writings on Judaism have been a source of widespread controversy.