In a speech yesterday, veteran Harvard Law School professor Alan M. Dershowitz said that his longtime rival, retired MIT linguist Noam Chomsky, was “a Holocaust denier, a denier of history, a denier of reality and the truth.”

While the remarks are among the more vitriolic uttered by professors around Harvard, they are reflective of harsh words that the two have been exchanging for decades. (While Chomsky largely avoided Dershowitz in his speech last night, he did take a swipe at Dershowitz’s book, “The Case for Israel.”)

While the two might seem to have some common ground—both are Jewish civil libertarians who consider themselves member of the left—they diverge sharply when it comes to Israel. Chomsky, a cognitive linguistic, is noted for his heated criticisms of both the Jewish state and American foreign policy, while Dershowitz has emerged as one of Israel's most prominent ideological supporters in the United States.

The history of attacks between the two dates back decades. Some examples include:

Dershowitz: “I have written extensively about his zealous anti-Zionism and his flirtations with neo-Nazi revisionism and Holocaust denial.” (2002)

Chomsky: “Dershowitz is not only a remarkable liar and slanderer, but also an extreme opponent of elementary civil rights.” (2006)

Dershowitz [regarding Chomsky’s claim that American newspapers had not covered some attacks on Palestinians]: “Why would the newspapers not cover these stories? They are figments of Chomsky’s imagination. [He lives] on Planet Chomsky where the news reflects his views on the world.” (2005)

Chomsky: “[Dershowitz] has produced a series of hysterical tirades and lies concerning some entity in his fantasy world named ‘Chomsky,’ who lives on ‘Planet Chomsky.’ That is his standard style when he is exposed.” (2006)

—Staff writer Paras D. Bhayani can be reached at pbhayani@fas.harvard.edu.