Arab Knesset member Haneen Zoabi has compared IDF soldiers to Islamic State terrorists.“They [Islamic State terrorists] kill one by one with their knife, and in the IDF they kill dozens of Palestinians with one button,” the Balad party MK told Channel 2 on Sunday.In response, several Likud lawmakers called to punish Zoabi and take away her freedom of speech.Zoabi’s comparison of the IDF to Islamic State was admittedly outrageous. It notably coincided with news reports that the IDF had permitted the daughter of Hamas leader Ismail Haniyeh to leave the Gaza Strip so that she could receive medical treatment at Sourasky Medical Center’s Ichilov Hospital in Tel Aviv.This is not the first time Zoabi has used her freedom of speech in the most despicable way. A Knesset Channel poll conducted over the summer found that 89 percent of Jewish Israelis think Zoabi’s citizenship should be revoked, while 10% oppose such a move.But when we consider curtailing free speech, it is imperative that we take into consideration exactly what is at stake.Freedom of speech has a long and illustrious tradition in Western culture, from John Milton’s Areopagitica, a speech given by the poet before Parliament in 1644, during the English Civil War, in which he opposed censorship, to the writings of the founding fathers of America, to John Stuart Mill’s 1859 essay On Liberty. And while the common tendency when discussing freedom of speech is to emphasize the right of the speaker to make his or her point, it is no less important to note, as Milton, Mill and others have, that freedom of speech includes the right to listen and to hear.If all society were agreed on the truth and beauty and value of one proposition – all except one person – it would be most important, in fact it would become even more important, that that one heretic be heard, because we would benefit from his perhaps outrageous or appalling view, Mill said. Freedom of speech is meaningless unless it means the freedom of the person who thinks differently.By protecting the freedom of speech of Holocaust deniers, Flat Earth Society members and people such as Zoabi, we foster a culture in which people are forced to think about why they know what they know. In rejecting claims made by, say, British historian David Irving, we have the opportunity to get back to first principles. We might even end up learning more about the Holocaust in the process.More critically, however, when curtailing freedom of speech, we must ask ourselves to whom we are willing to entrust the power to decide where the line runs between permitted and prohibited speech. Should lawmakers Israel Katz, Miri Regev or Danny Danon be the one who decides? Who will determine in advance what the harmful consequences would be, so that we can ban certain types of speech before they are uttered? The danger is obvious. As soon as we appoint a person or a group of persons to censor speech, we create, at least in potential, our own Big Brother, a rod for our backs.We should give the public a bit more credit for its ability to draw distinctions. A year ago Tuesday, Zoabi ran in the Nazareth mayoral election. She was hoping to cash in on her media exposure in the wake of her Mavi Marmara escapade and her volatile speeches in the Knesset. She ended up receiving less than 10% of the vote. Nazareth’s residents are, apparently, more interested in sewage, municipal taxes and education than in Zoabi’s radical politics. Her chances of winning might have been greater if she had been banned from the Knesset.Zoabi must know that the threat to freedom of speech is not coming solely or primarily from a group of Likud politicians. Critics of Islam are regularly bullied into silence in Western cities, including in the US. In September 2012, for instance, the Obama administration asked Google to reconsider its decision not to ban a video called ridiculing Muhammad called Innocence of Muslims that set off violent protests in the Arab world.We can only wonder how many newspapers, artists, scholars, publishers and speakers censor themselves to avoid hurting the feelings of radical Muslims determined to be offended.But just as we must not allow the Islamists whom Zoabi is so quick to protect bully us into relinquishing our hard-earned freedoms, so, too, must we avoid the temptation to stifle Zoabi’s freedoms, even if she fails to appreciate the gift of living in a democracy.