According to Thomas Jefferson, when a government becomes abusive and destructive of the people's rights, it is the people's duty to throw off that government and establish a new one that will better secure their safety and happiness. Jefferson emphasizes that governments are instituted to secure the rights of the people, and whenever a government fails in this fundamental purpose by a long train of abuses and usurpations, the people not only have the right but also the duty to overthrow such a government to protect their future security. This is asserted in the Declaration of Independence, where Jefferson states that it is the right and duty of the people "to alter or to abolish it, and to institute new Government" when the existing government becomes tyrannical. He also discusses the principle of prudence, meaning that governments should not be changed for light causes but when abuses become severe and persistent, action is necessary. This duty is grounded in the idea that the legitimacy of government comes from the consent of the governed, and that consent is withdrawn when the government no longer secures their rights.
