Each of the three distinct parties (as do also the Bell and Everett party) assume to stand upon the common ground of the constitution and to justify their principles and measures by that sacred instrument, "the palladium of American liberty." 1st. The Breckinridge or Southern sectional theory, claiming the Dred Scott decision as its justification, is, that slavery is a benign national institution, to be fostered and protected by the Federal government "wherever its constitutional authority extends;" and the logical sequence from the Dred Scott decision, as construed in the South, is, that this national institution involves an inviolable right of property, and is carried by force of the constitution into _all the States and Territories_, and is there to be protected by the Federal government, and this idea is entirely consistent with the Breckinridge platform adopted at Baltimore on the 28th June last. A necessary result of the establishment of this theory will be the reopening of the African slave trade. 2d. The Lincoln and Seward or Northern sectional theory, is, that slavery is a relic of barbarism, antagonistic to the principles and policy of the nation, and is to be annoyed, assailed, and ultimately annihilated by the Federal government wherever its constitutional authority extends. To sum up the two theories in a few words: Slavery, according to Breckinridge and his school, is a _national good_, to be encouraged and protected by the national strong arm. Slavery, according to Lincoln and Seward, is a _national evil_, gigantic and portentous, to be combatted and slain by the same strong arm. That the South will permit slavery to be abolished in all the States by violence or starvation; or that the North will permit slavery to be established in all the States by judicial decision or otherwise, no man in his senses believes--hence looking to the legitimate results _of their doctrines_, both the Breckinridge and Lincoln parties _are essentially disunion parties_. Constant conflict and ultimate disunion are the natural sequents of their antagonism. As neither can hope to conquer the other, the Union, the common bond and roof tree of both, must be divided and fall.