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.

The Declaration [of Independence] was a committee report, and [Tomas] Jefferson was simply the draftsman. [John] Adams's crucial role in bringing about independence in the Continental Congress has tended to get forgotten.

Americans, [John Adams] wrote in 1780, believed that their "revolution is as much for the benefit of the generality of Mankind in Europe, as for their own."

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.

The relationship between [John] Adams and [Tomas] Jefferson was extraordinary. They differed on every conceivable issue, except on the Revolution and the love of their country.

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

[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.