DEAR BOSTON: Your personality test has been completed, and the results aren’t pretty.

Actually, they are downright embarrassing.

Two psychologists conducted a national survey, asking Americans questions designed to measure 24 “character strengths.’’ They grouped some of these strengths, like gratitude and valuing emotional connections, as “strengths of the heart’’ - a fancy way of saying kindness. And then, for each of the nation’s 50 largest cities, they calculated an average score.

The conclusion: Boston came in at number 50. As in, dead last. As in, none of the country’s other major cities - not New York, not Los Angeles, not even Washington, D.C. - can match us for sheer smallness of spirit. We are officially the capital of mean.

Now it would be easy, in typical Boston fashion, to get defensive at this point. Who do these people think they are - these outsiders, no less - taking potshots at our fair city? But there is a vital message here, one that we all need to hear. And I can assure you that these particular outsiders, the University of Michigan’s Nansook Park and Christopher Peterson, don’t have anything against us.

“Boston is a great city,’’ insists Peterson, even as he admits our last place finish is “quite striking.’’

Three potential explanations suggest themselves. The first is the city’s peculiar history, or what Boston College history professor Thomas O’Connor calls “a whole series of periods of division, hatred, and separations that have shaped Boston for almost 400 years.’’ The Puritan founders, O’Connor points out, believed in a God who had selected a few, the elect, for heaven, and the rest for hell.

This founding tribal idea, O’Connor and others argue, has been reinforced in successive eras. When Irish Catholics began to pour into the city, they were met with vicious discrimination. Then, by the late 19th and early 20th century, this nativist thinking found new targets in the Italians and the Jews, and, later, other groups. The city also has a deep history of overlapping economic and religious divisions - Protestants, who ran economic institutions, versus Catholics, who controlled the political machine. And then there was busing.

Other cities, of course, have experienced division and conflict, but any fair reading of history suggests that Boston has a remarkable record of achievement in this regard. Boston is, famously, “a city of neighborhoods,’’ of segregation, and habits of mind are hard to break.

A second explanation may be, oddly enough, the weather. The pair found a link between warmth of personality and average temperature, according to their American Psychologist paper. El Paso had the highest “strength of the heart,’’ and other leaders included Miami and Honolulu. Perhaps, he offers, warmer city residents form more connections because they see each other more.

There may be something to that. By the end of February, I am usually flipping between feeling homicidal and suicidal, and I am not alone. And then every spring on my little street, we all emerge blinking from our holes and staring in amazement at each other’s children, who seem to have grown several inches since last we saw them.

A third possibility is selective migration. Boston’s independent streak and Yankee reticence attract the like minded, folks who are probably less inclined toward open-ended emotional connections.

The costs of our pinched outlook have not been quantified, but surely the ledger of losses is long, and includes great difficulties in solving common problems, and a river of talented people who leave for friendlier shores.

Smart observers suggest that Boston has been improving, becoming less fractured, less mean. But the city still has a problem at its core. Which means that we, its residents, have a problem. In their paper, the researchers quote Shakespeare, “What is the city but the people?’’ And at the moment, Boston is a great city that has, to quote that other great poet, Dr. Seuss, a heart that is “two sizes too small.’’

The Grinch chose to reform himself. Will we?

Gareth Cook can be reached at cook@globe.com. Follow him on Twitter@garethideas.

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