On this day in 1825, Thomas Jefferson wrote a letter in response to a query from Henry Lee on the purpose of the Declaration of Independence. Jefferson was known as the primary author of that document. His account of what the Declaration intended emphasizes that the principles it expressed were shared by all those supporting the Revolutionary cause. It was “an expression of the American mind,” he said, one that synthesized ideas drawn not only from political philosophers read by Americans but also from the colonists’ own experience. The Declaration was to express “the common sense of the subject.” Having been allowed during much of the colonial period to govern their own affairs semi-autonomously, Americans had arrived at an understanding of their own rights. These rights, and America’s assertion of independence, rested on principles that the Declaration made clear.