"They are not to do anything they please to provide for the general welfare, but only to lay taxes for that purpose. To consider the latter phrase not as describing the purpose of the first, but as giving a distinct and independent power to do any act they please which may be good for the Union, would render all the preceding and subsequent enumerations of power completely useless. It would reduce the whole instrument to a single phrase, that of instituting a Congress with power to do whatever would be for the good of the United States; and as they would be the sole judges of the good or evil, it would be also a power to do whatever evil they please...Certainly no such universal power was meant to be given them. It was intended to lace them up straightly within the enumerated powers and those without which, as means, these powers could not be carried into effect." 

-- Thomas Jefferson, Opinion on a National Bank, 1791

"[I]n questions of power then, let no more be heard of confidence in man, but bind him down from mischief by the chains of the Constitution..."

-- Thomas Jefferson, Kentucky Resolutions, 1798

"It is the manners and spirit of a people which preserve a republic in vigor. A degeneracy in these is a canker which soon eats to the heart of its laws and constitution."

-- Thomas Jefferson, Notes on the Virginia Query 19, 1781

"The steady character of our countrymen is a rock to which we may safely moor; and notwithstanding the efforts of the papers to disseminate early discontents, I expect that a just, dispassionate and steady conduct, will at length rally to a proper system the great body of our country. Unequivocal in principle, reasonable in manner, we shall be able I hope to do a great deal of good to the cause of freedom and harmony."

-- Thomas Jefferson, letter to Elbridge Gerry, 1801

"Laws that forbid the carrying of arms ... disarm only those who are neither inclined nor determined to commit crimes... Such laws make things worse for the assaulted and better for the assailants; they serve rather to encourage than to prevent homicides, for an unarmed man may be attacked with greater confidence than an armed man."

-- Cesare Beccaria, On Crimes and Punishment, quoted by Thomas Jefferson in Commonplace Book

"If we can prevent the government from wasting the labors of the people, under the pretence of taking care of them, they must become happy."

-- Thomas Jefferson, letter to Thomas Cooper, 1802

"I think we have more machinery of government than is necessary, too many parasites living on the labor of the industrious."

-- Thomas Jefferson, letter to William Ludlow, 1824

"It would reduce the whole instrument to a single phrase, that of instituting a Congress with power to do whatever would be for the good of the United States; and as they would be the sole judges of the good or evil, it would be also a power to do whatever evil they please. Certainly no such universal power was meant to be given them. It [the Constitution] was intended to lace them up straightly within the enumerated powers and those without which, as means, these powers could not be carried into effect."

-- Thomas Jefferson, Opinion on a National Bank, 1791