What are the major arguments put forward by pro slavery advocates

Pro-slavery arguments were that blacks weren't really human, almost that they were designed by God as beasts of burden.  Slavery was endorsed by the Bible (both Old and New Testaments!) and slavery gave blacks a chance to do productive work (the Devil finds work for idle hands!) and to learn about Jesus and therefore be saved.  And also that slavery was an economic necessity in the South, and especially to the cotton industry which was the great American economic engine.

The argument against this was that blacks were just as human as whites are, and that slavery violates their 'human rights' of life, liberty and the pursuit of happiness.  Nobody has the right to -own- another human being and just use them as they please.

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