By the time [John Adams] came to write his Defence of the Constitutions of the United States in 1787 he had as dark a view of the American character as that of any critic in our history.

[John Adams] experience with the French philosophers only convinced him further of the need for a bicameral legislature representing the two principal social orders and, equally important, an independent executive.

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 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.

[John] Adams's letters to [his wife] Abigail are wonderful. In his letters, he is loving, humorous, preachy, learned, and saucy. He speaks to her with almost complete abandon, revealing all of his sensuous and vulnerable nature.

It was [John's Adams] Massachusetts constitution if anything that influenced people.