The phrase "All men are created equal" is arguably the best-known phrase in any of America's political documents, since the idea it expresses is generally considered the foundation of American democracy. The phrase in context in the opening of the Declaration of Independence, penned by Thomas Jefferson in 1776, reads 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.

These statements illustrate the idea of natural rights, a philosophical concept coming into favor in America as well as elsewhere. Many of the ideas in the Declaration were, in fact, borrowed from John Locke, the great English liberal political philosopher. In fact, Jefferson was accused of quoting him verbatim. Locke, however, refered to "Life, Liberty, and Property," rather than the pursuit of happiness.

Declaring the equality of all men did not, however, prevent the United States from continuing the widespread practice of slavery. Indeed, president Lincoln relied on the Declaration of Independence when making the case that slavery went against the deepest commitments of the American nation. Though he did so throughout the 1850s and into his presidency, the most famous example can be found in the Gettysburg Address:

Fourscore and seven years ago our fathers brought forth on this continent a new nation, conceived in liberty and dedicated to the proposition that all men are created equal.

The phrase has since been considered a hallmark statement in democratic constitutions and similar human rights instruments, many of which have adopted the phrase (or variants thereof). Examples:

• Declaration of the Rights of Man and of the Citizen (1789), article 1: Men are born and remain free and equal in rights. Social distinctions can be founded only on the common utility.
• Universal Declaration of Human Rights (1948), article 1: All human beings are born free and equal in dignity and rights