Alexander H. Stephens said this quote

“ I recollect once of having heard a gentleman from one of the northern States, of great power and ability, announce in the House of Representatives, with imposing effect, that we of the South would be compelled, ultimately, to yield upon this subject of slavery, that it was as impossible to war successfully against a principle in politics, as it was in physics or mechanics. That the principle would ultimately prevail. That we, in maintaining slavery as it exists with us, were warring against a principle, a principle founded in nature, the principle of the equality of men. The reply I made to him was, that upon his own grounds, we should, ultimately, succeed, and that he and his associates, in this crusade against our institutions, would ultimately fail. The truth announced, that it was as impossible to war successfully against a principle in politics as it was in physics and mechanics, I admitted; but told him that it was he, and those acting with him, who were warring against a principle. They were attempting to make things equal which the Creator had made unequal. ”