Slavery existed for thousands of years, in all sorts of societies and all parts of the world. To imagine human social life without it required an extraordinary effort. Yet, from time to time, eccentrics emerged to oppose it, most of them arguing that slavery is a moral monstrosity and therefore people should get rid of it. Such advocates generally elicited reactions that ranged from gentle amusement to harsh scorn and violent assault.

When people bothered to give reasons for opposing the proposed abolition, they advanced many different ideas. In the first column of the accompanying table, I list ten such ideas that I have encountered in my reading. At one time, countless people found one or more of these reasons an adequate ground on which to oppose the abolition of slavery.