美国的黑人奴隶制与美国的自由主义、共和主义和民主思想存在着无法解释的巨大矛盾。而且,由于美国史学界经常受到时代思潮、学术发展、种族关系、舆论环境、个人价值取向和其它诸多因素的影响,美国的黑人奴隶制研究长期处于流派纷呈、莫衷一是的状态之中。 There is an unspeakable huge contradiction between the black slavery of the United States and liberalism, republicanism and democratic thinking in the United States. Moreover, since the American historians are often influenced by the trend of times, academic development, ethnic relations, public opinion environment, personal value orientation and many other factors, the study of black slavery in the United States has long been in a state of mixed genre and incomprehensible.