In response to criticism of his comment that a Muslim American should not be president, Republican presidential candidate Ben Carson is saying he's a victim of political correctness. (Reuters)

There are lots of definitions of stereotyping. To Merriam-Webster, it’s believing, “unfairly that all people or things with a particular characteristic are the same.” To social scientists, it’s “a negative attitude toward a particular social group and its members.”

Most people know it when they see it. And many saw it, and more, in Republican presidential candidate Ben Carson’s assertion on  NBC’s Meet the Press that the president should not be Muslim. Asked by Chuck Todd whether a presidential candidate’s faith should matter, Carson replied, “I guess it depends on what that faith is. If it’s inconsistent with the values and principles of America, then of course it should matter.” Carson also told Todd that he didn’t not think Islam was consistent with the Constitution. Carson would not, he told Todd Sunday, “advocate that we put a Muslim in charge of this nation.” (Speaking Tuesday, Carson said his earlier comments had been taken out of context.)

[VIDEO: Carson draws fire for comments on Muslims]

In his classification of a whole group of people as somehow unfit for high public office, Carson is definitely in the mainstream of history — history, that is, from the 19th into the mid-20th century. All through that era, a succession of minorities of Irish, Jewish, Chinese or African descent were deemed by large numbers of Americans to hold to traditions, religions or racial characteristics that others deemed incompatible with American values and democratic traditions.

It’s best documented by Alexander Keyssar in “The Right to Vote: The Contested History of Democracy in the United States.”  African Americans were “widely believed to be inferior and lacking in potential Republican virtues,” he writes, and incapable — a “peculiar people,” as one New York politician put it in 1821 — of participating in the political system “with any sort of discretion, prudence or independence.” Irish and other working class immigrants were deemed to be “controlled by the Pope.” Others, like Jews, were targeted as socialists in turn-of-the century New York, a situation dealt with by scheduling voting registration “on the Jewish sabbath and on the holy holiday of Yom Kippur.”

The fears and stereotypes extended even more easily into schools and workplaces, which were largely unrestricted in their capacity to treat people not as individuals but as members of groups that bore undesirable characteristics justifying discrimination in one form or another, particularly against African Americans.

Given that history, the idea of an African American politician stereotyping another group of people and declaring them somehow unfit for the presidency, was striking to Keyssar, a professor at Harvard University’s Kennedy School of Government. There “is certainly a profound historical irony here,” he said in an interview with The Washington Post.

“I think somehow in Carson’s mind there’s a difference between something like race, which is an ascriptive category, something that someone can’t choose,” and religion, “which is indeed a matter of choice.” Carson’s explanations since his Meet the Press comments tend to support that theory: He has said that a moderate Muslim who renounced radical Islam and who would put the Constitution before their faith would be worthy of consideration.

[Carson softens tone on Muslims, says he was taken out of context]

Carson’s utterances, said Keyssar, “fall into this tradition of fearing an ‘other,’ whether the other be black or Chinese or, god knows, Irish ….It wasn’t that they were just Catholic. They were the ‘other’ ….It’s a kind of group characteristic. That I would not trust any Muslim to be president.”

More ironic still, and deeply puzzling under the circumstances, is that Carson, who often dismisses complaints about his comments as “political correctness,” has had his own complaints about stereotyping, which as he describes them in his various autobiographical books, he took quite seriously.  He felt the sting and it hurt.

In “Gifted Hands,” Carson describes what he called a “shocking episode” of racial humiliation. He was in the eighth grade at a predominantly white school, where each year, the school handed out certificates to the student with the highest academic achievement. In that year, it happened to be him.

He was proud as his name was called to come up and receive his hard-earned prize. But the teacher, after handing it to him, remained up in front of the entire student body and looked out across the auditorium. “‘I have a few words I want to say right now,’ she began, her voice unusually high. Then, to my embarrassment, she bawled out the White kids because they had allowed me to be number one. ‘You’re not trying hard enough’ she told them.

“While she never quite said it in words, she let them know that a Black person shouldn’t be number one in a class where everyone else was White.” Why, he wondered, “would she say all these harsh things?”

“Was she so ignorant,” he writes, “that she didn’t realize that people are just people?”

He recalls in “My Life,”  his brother being placed in a vocational track at school. “His grades were good enough for the college curriculum, but this was a predominately white school, and Mother was convinced that the counselor had made the fairly common assumption that blacks were incapable of college work. So Mother headed straight for the counselor’s office the next day.”

In “One Nation,” Carson recalls his resentment at the stereotype of the “uppity” black. “Since whites held the most powerful and lucrative positions in society, most of them were certainly in no hurry to share those positions with others. Blacks, on the other hand, were becoming progressively more educated and therefore impatient to share the fruits of their labors. This eagerness,” he writes, “was frequently misinterpreted by whites who coined the term uppity to characterize those blacks who, in their opinion, didn’t ‘know their place.'”

And he rails against another stereotype: “It was common for whites to believe that blacks were dirty, unintelligent, and sexually promiscuous. These beliefs informed hiring practices and property distribution.” And, he adds in a passage that seems particularly telling in light of his comments on Muslims, “many of the whites in those days found ways to rationalize their unjust treatment of fellow human beings, arguing that they were not racists but rather protectors of traditional values.”

Stereotypes. He can remember, he recounts in “One Nation, “when “I would be walking in a white neighborhood and in short order a police car would show up, undoubtedly summoned by a concerned onlooker. Unfortunately, this and worse still happens today, as evidenced by the Trayvon Martin case.” The “real tragedy,” of that case, he added, “is that a young life was lost and another life ruined because both individuals made assumptions about the other that were probably untrue.”

And it didn’t quit. As he made his way through Yale, Michigan and won a neurosurgery residency at Johns Hopkins and became a physician at Johns Hopkins, he encountered grating stereotypes. “Even in the 1970s at a prestigious institution like Johns Hopkins, people were not accustomed to seeing a black doctor. Sometimes it was almost humorous; other times, more disturbing. More than once, nurses thought I was an orderly or physical therapist — anything but a doctor.”

On top of that, “there were patients who didn’t want a black doctor caring for them.”

After a round of criticism for his comments on Muslims, including a highly critical denunciation from the Anti-Defamation League, and from two Muslim members of Congress, among others, Carson has not backed down.

But he has elaborated. It’s not just Muslims he wouldn’t vote for, he told Fox New’s Sean Hannity. It’s anyone “whose faith might interfere with them carrying out the duties of the Constitution. “If you’re a Christian and you’re running for president and you want to make this [country] into a theocracy, I’m not going to support you.”

As for Muslims, he might consider it. “If someone has a Muslim background, and they’re willing to reject those tenets and to accept the way of life that we have, and clearly will swear to place our Constitution above their religion, then of course they will be considered infidels and heretics, but at least I would then be quite willing to support them.”