When television host Bill Maher declares on his weekly show that “the Muslim world . . . has too much in common with ISIS ” and guest Sam Harris says that Islam is “the mother lode of bad ideas,” I understand why people are upset. Maher and Harris, an author, made crude simplifications and exaggerations. And yet, they were also talking about something real.

I know the arguments against speaking of Islam as violent and reactionary. It has a following of 1.6 billion people. Places such as Indonesia and India have hundreds of millions of Muslims who don’t fit these caricatures. That’s why Maher and Harris are guilty of gross generalizations. But let’s be honest. Islam has a problem today. The places that have trouble accommodating themselves to the modern world are disproportionately Muslim.

In 2013, of the top 10 groups that perpetrated terrorist attacks, seven were Muslim. Of the top 10 countries where terrorist attacks took place, seven were Muslim-majority. The Pew Research Center rates countries on the level of restrictions that governments impose on the free exercise of religion. Of the 24 most restrictive countries, 19 are Muslim-majority. Of the 21 countries that have laws against apostasy, all have Muslim majorities.

There is a cancer of extremism within Islam today. A small minority of Muslims celebrates violence and intolerance and harbors deeply reactionary attitudes toward women and minorities. While some confront these extremists, not enough do so, and the protests are not loud enough. How many mass rallies have been held against the Islamic State (also known as ISIS) in the Arab world today?

The caveat, “Islam today,” is important. The central problem with Maher’s and Harris’s analyses are that they take a reality — extremism in Islam — and describe it in ways that suggest it is inherent in Islam. Maher says Islam is “the only religion that acts like the Mafia, that will [expletive] kill you if you say the wrong thing, draw the wrong picture or write the wrong book.” He’s right about the viciousness but wrong to link it to “Islam” — instead of “some Muslims.”

Harris prides himself on being highly analytical — with a PhD, no less. I learned in graduate school that you can never explain a variable phenomenon with a fixed cause. So, if you are asserting that Islam is inherently violent and intolerant — “the mother lode of bad ideas” — then, since Islam has been around for 14 centuries, we should have seen 14 centuries of this behavior.

Harris should read Zachary Karabell’s book “Peace Be Upon You: Fourteen Centuries of Muslim, Christian and Jewish Conflict and Cooperation.” What he would discover is that there have been wars but also many centuries of peace. Islam has at times been at the cutting edge of modernity, but like today, it has also been the great laggard. As Karabell explained to me, “If you exclude the last 70 years or so, in general the Islamic world was more tolerant of minorities than the Christian world. That’s why there were more than a million Jews living in the Arab world until the early 1950s — nearly 200,000 in Iraq alone.”

If there were periods when the Islamic world was open, modern, tolerant and peaceful, this suggests that the problem is not in the religion’s essence and that things can change once more. So why is Maher making these comments? I understand that as a public intellectual he feels the need to speak what he sees as the unvarnished truth (though his “truth” is simplified and exaggerated). But surely there is another task for public intellectuals as well — to try to change the world for good.

Does he really think that comparing Islam to the Mafia will do this? Harris says that he wants to encourage “nominal Muslims who don’t take the faith seriously” to reform the religion. So, the strategy to reform Islam is to tell 1.6 billion Muslims, most of whom are pious and devout, that their religion is evil and they should stop taking it seriously?

That is not how Christianity moved from its centuries-long embrace of violence, crusades, inquisitions, witch-burning and intolerance to its modern state. On the contrary, intellectuals and theologians celebrated the elements of the religion that were tolerant, liberal and modern, and emphasized them, while giving devout Christians reasons to take pride in their faith. A similar approach — reform coupled with respect — will work with Islam over time.

The stakes are high in this debate. You can try to make news or you can make a difference. I hope Maher starts doing the latter.

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