[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."

A mutual friend, Benjamin Rush, brought [Tomas Jefferson and John Adams] together in 1812, and they went on to exchange letters for the rest of their lives. But in their correspondence they tended to avoid the most controversial issues, such as slavery.

[John] Adams's letters reveal his persistence and determination to win over the Dutch against all odds and to convince them and the other peoples of Europe of the potential greatness of the United States and of the importance of the Revolution to the world.

[John Adams] always felt that his contribution to bringing about independence went unappreciated, especially after the 1790s when [Tomas] Jefferson began to be lauded as the "author" of the Declaration of Independence.

If history teaches anything, it teaches humility.

The Massachusetts constitution was written much later than the other revolutionary state constitutions, and thus it avoids some of the earlier mistakes. The executive is stronger, with a limited veto; the senate is more formidable; and the judiciary is independent.

Creating senates, the French critics said, implied that there was another social order besides the people represented in the houses of representatives. [John] Adams actually agreed with that implication and argued that the aristocracy and the people had to have separate houses; this was the only way the power of the aristocracy could be contained.