Benjamin Franklin was a slaveowner for much of his life until he visited a school for black children and discovered that African ignorance was not inherently natural but come from lack of education, slavery and negative environments.
Thomas Jefferson, a slaveholder, refused to recognize Haiti after the Haitian Revolution and imposed a trade embargo on them to ensure their economic failure, for fear that a successful slave revolt in the West Indies would inspire slaves in the US
Jefferson’s first draft of the Declaration of Independence criticized King George III for enslaving Africans, and for over-ruling Virginia’s attempt to ban Slavery. In it, Jefferson called slavery a “cruel war against human nature".
James Buchanan regularly bought slaves with his own money in Washington, D.C. and quietly freed them in Pennsylvania
Benjamin Franklin was president of an abolitionist society and required his daughter to free her slave in order to get her inheritance.
Abolitionism is essentially a proposal to destroy the right and extinguish the principle of sell-government for which our forefathers waged a seven years' bloody war, and upon which our whole system of free government is founded.