Q: A coworker points out that the Founding Fathers used “insure” incorrectly. Of course no one wants to say Thomas Jefferson was wrong! And as you note, “ensure” and “insure” have much in common.
A: The Constitution and its Preamble were written in 1787, and the language, capitalizations, and spellings reflect the usage of the day. The Preamble reads:
“We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.”
We’ve reproduced the original 1787 spellings, quoting from the document held in the National Archives. The spellings “defence” (still used in British English) and “insure” were common usage in the 18th century.
As we’ve written before on our blog, in current usage to “insure” is to issue or buy insurance against financial loss, while to “ensure” is to make certain of something.
That’s the usual practice, and the one recommended by usage guides, though dictionaries say the two terms are sometimes used interchangeably.
Meanwhile, in current usage to “assure” means to reassure or remove doubt, though the British sometimes use the term in the technical sense of to underwrite financial loss.
As you can see, English usage changes over time!
Thomas Jefferson used “insure” in the general sense in a memoir he wrote in 1825, cited in the Oxford English Dictionary: “A recurrence to these letters now insures me against errors of memory.”
Jefferson, by the way, didn’t write the Preamble or any other part of the Constitution. He was ambassador to France at the time, and was out of the country during the Constitutional Convention of 1787.
But he did write the Declaration of Independence in 1776, though a few touches were added by John Adams and Benjamin Franklin.
The authorship of the Preamble and much of the rest of the Constitution is credited to another of the Founders, Gouverneur Morris, who was a Pennsylvania delegate to the 1787 convention.
In the past, we’ve answered several other questions about the Preamble, in case you’re interested.
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