The doctrine of popular sovereignty was propounded by Jefferson in the American Declaration of Independence and was incorporated in the Preamble of the Constitution by asserting that government derived its authority from the consent of the governed. An echo of it is found in Abraham Lincoln's First Inaugural Address: “This country, with its institutions, belongs to the people who inhabit it. Whenever they shall grow weary of the existing government they can exercise their constitutional right of amending it, or their revolutionary right to dismember or overthrow it." This is Rousseau's theory of popular sovereignty in radical form. Since then popular sovereignty has become, as Bryce says, "The basis and watchword of democracy”