A copy of The Declaration Of Independence is displayed at the New York Public Library on July 1, 2014 (Andrew Burton/Getty Images)

Danielle Allen is a political theorist at the Institute of Advanced Study and a contributing columnist for The Post. Her research will be the focus of a free conference on the Declaration of Independence titled “Punctuating Happiness,” on June 23 at National Archives in Washington.

For all that we talk about “original” founding documents, when it comes to the Declaration of Independence at least, we’ve had multiple versions since the earliest days of the revolution. The most important difference among these versions appears in the sentence about self-evident truths.

The manuscripts written out by John Adams and Thomas Jefferson; the version voted on by Congress, as attested to in the official minutes recorded by Charles Thomson; and the official poster printed up by John Dunlap at Congress’s request, on July 4 and 5, 1776, record a very long second sentence, reading as follows:

“We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness; that to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed; that whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.”

This lengthy sentence is a remarkably cogent expression of the theory of revolution that developed in early modern political thought. The people preserve their right to ensure that their rights are secured. When governments fail to secure those rights, the people may alter their government or, if it comes to it, abolish it and start over.

Yet on July 6, Philadelphia printer Benjamin Towne — who had obtained a copy of the Declaration we know not how — printed an unauthorized version that broke that long sentence into two by placing a period after “pursuit of happiness.” Towne scooped Dunlap, who didn’t get the Declaration into his own paper until July 8. As the first newspaper printing, Towne’s version was circulated extensively and read like this:

“We hold these truths to be self-evident, That all men are created equal; that they are endowed, by their Creator, with certain unalienable rights; that among these are life, liberty, and the pursuit of happiness. That to secure these rights, governments are instituted among men, deriving their just powers from the content of the governed . . .

In Towne’s printing, both the requirement that government balance the individual right to pursue happiness with the collective safety and happiness of the people and the accompanying theory of revolution drift out of focus. The period after pursuit of happiness leads us to disconnect the opening premise about individual rights from the argument for the positive value of good government and the all-important conclusion about altering governments that fail us. Last summer, I stood behind a group of high school students at an exhibit about the Declaration. They began reading one of the versions of the text with the period. When they got to “pursuit of happiness,” they lifted their hands in the air, shouted “yes,” and were gone. They got the point about individual rights but not the people’s responsibility to determine principles and organizational forms that achieve their shared safety and happiness.

Six months after Towne printed his version, another printer used Towne’s text as the starting point for an official version. In January 1777, after the Continental Congress scrambled to Baltimore because the British had pressed into Philadelphia, Congress commissioned local printer Mary Katherine Goddard to create 13 copies of the Declaration, one for the official archives of each newly minted state. Goddard served as Baltimore’s postmistress and leading newspaper woman. She had already printed a version of the Declaration in her newspaper on July 10 that followed Towne’s printing. She did this again when she printed an authorized Declaration for each state capital.

Thus, by January 1777, the infant country had four official versions of its Declaration of Independence. There was the text by Thomson, Congress’s secretary, in Congress’s official minutes book. There was Dunlap’s printing for Congress. There was the parchment done by calligrapher Timothy Matlack that members of Congress signed, now a national treasure held by the National Archives. And there were the 13 copies that Goddard printed.

Two of these — the Thomson version and the Dunlap version — have a list of self-evident truths set out as a single sentence ending in “their safety and happiness,” and conveying the theory of revolution. One of these, Goddard’s printing, has a period after “pursuit of happiness,” giving us a rather different second sentence.

But what about the parchment? What did Matlack write? We actually don’t know just how he punctuated that second sentence. The text is poorly legible at that spot. There is a mark after “pursuit of happiness,” but without some miraculous discovery from technologies such as hyper-spectral imaging, we can’t say for certain whether it’s a period or a comma.

In short, we have a diverse textual tradition for the Declaration of Independence, and we’ve had it since July 6, 1776, when Towne’s unauthorized newspaper printing spread far and wide.

The Declaration of Independence is a required text in the Common Core, and all versions of the SAT, starting in 2016, will engage with it in some way. Just how should we teach this text, given its diverse tradition?