The framers knew they could not foresee the future, so they built in a way to change the Constitution. They made it possible, but deliberately, famously hard. It has worked just 27 times.
An amendment is a formal change or addition to the Constitution. The framers knew their document was imperfect and that times would change, so Article V lays out how to alter it, without making it so easy that the fundamental law could shift on a passing whim.
The usual path has two steps, both demanding. An amendment must be proposed by a two-thirds vote of both houses of Congress, then ratified by three-fourths of the states. Broad national consensus is required at every stage.
That difficulty is the point. By design, no simple majority and no single faction can rewrite the rules. The high bar protects the Constitution's stability, ensuring change comes only with overwhelming and sustained agreement.
The results show how rare success is. In more than two centuries, thousands of amendments have been proposed and only 27 ratified, the first ten arriving together as the Bill of Rights. Some, like ending slavery and guaranteeing the vote, remade the nation.
