As early as 1776, [John Adams] expressed his doubts about America's capacity for virtue. "I have seen all along my Life, Such Selfishness, and Littleness even in New England, that I sometimes tremble to think that, altho We are engaged in the best Cause that ever employed the Human Heart, yet the Prospect of success is doubtfull not for Want of Power or of Wisdom, but of Virtue."

[John Adams] is impressed with [Tomas] Jefferson's learning, but noted his silence during the debates in the Congress: "I never heard him utter three Sentences together."

I think [John Adams's] influence on the federal Constitution was indirect. Many including James Madison mocked the first volume of Adams's Defence of the Constitutions of the United States in 1787. But his Massachusetts constitution was a model for those who thought about stable popular governments, with its separation of powers, its bicameral legislature, its independent judiciary, and its strong executive.

Perhaps more significant than his experience in Europe, though, was [John] Adams's experience in his own country, and his extensive reading on the history of the English constitution. In 1779, he had an opportunity to try out his ideas by framing the Massachusetts constitution.

[John] Adams said his objective in writing his Defence of the Constitutions of the United States and his Davila essays was to counter what he thought was the unfair criticism of the American state constitutions made by the French philosophers, especially [Anne Robert Jacques] Turgot.

[John] Adams identified himself with the political theories of [James] Harrington, [John] Locke, and [Charles-Louis] Montesquieu, whose ideas of constitutionalism, he believed, were applicable to all peoples everywhere; they were his contribution to what he called "the divine science of politics."

[John] Adams was the best and most colorful stylist among the Founders. Although [Tomas] Jefferson is widely regarded as the smoothest writer, Adams is by far the most engaging and imaginative.