Abolition of slavery
Many people have worked to abolish slavery, particularly since the 1800s (see abolitionists). The chief philosophical ground for abolition has been the idea that human beings are too valuable to be property, as well as the idea that human beings ought to control their own destiny. Much of this philosophy stems from religious views (as in Christianity), although Christianity, Judaism and Islam have each historically supported slavery. Belief in abolition has contributed to the foundation of some denominations such as the Free Methodist Church.
Another ground for abolishing slavery has been economic, and much ink has been spilled describing how various crusaders or factions have sought to profit financially by outlawing slavery. Indeed, Marxist and other historians have analyzed the American Civil War from this point of view (Charles Beard?).
Opposition to abolition has come primarily from people who profit personally from slave labor or the slave trade, including those who rely on goods produced by slaves, as well as from people who regard slaves as inferior beings suited to servitude.
See also: abolitionist, Underground Railroad