After [Tomas] Jefferson's defeat of [John] Adams in the presidential election of 1800, they didn't communicate with one another for more than a decade.

Again and again [Tomas] Jefferson deftly sidesteps many of [John] Adams's often provocative remarks. They both felt the correspondence, which was written for posterity, was too important to risk by being too candid with one another.

[John Adams] diary, of course, is even more revealing of his feelings. Both his letters to [his wife] Abigail and his diary tell us what he really thinks about people and events.

[John] Adams never had an optimistic view of human nature, and his experience in the Congress and abroad only deepened his suspicion that his fellow Americans might not have the character to sustain a republican government.

[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 and Tomas Jefferson] shared experience in 1775 - 1776 in bringing about the separation from Britain and their service in Europe cemented a friendship that in the end withstood the most serious political and religious differences that one could imagine, especially their differences over the French Revolution. It was probably Jefferson's obsession with politeness and civility that kept the relationship from becoming irreparably broken.

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.