"The general words above quoted would seem to embrace the whole human family, and if they were used in a similar instrument at this day would be so understood. But it is too clear for dispute, that the enslaved African race were not intended to be included, and formed no part of the people who framed and adopted this declaration; for if the language, as understood in that day, would embrace them, the conduct of the distinguished men who framed the Declaration of Independence would have been utterly and flagrantly inconsistent with the principles they asserted; and instead of the sympathy of mankind, to which they so confidently appeared, they would have deserved and received universal rebuke and reprobation.
Yet the men who framed this declaration were great men -- high in literary acquirements -- high in their sense of honor, and incapable of asserting principles inconsistent with those on which they were acting. They perfectly understood the meaning of the language they used, and how it would be understood by others; and they knew that it would not in any part of the civilized world be supposed to embrace the negro race, which, by common consent, had been excluded from civilized Governments and the family of nations, and doomed to slavery. They spoke and acted according to the then established doctrines and principles, and in the ordinary language of the day, no one misunderstood them. The unhappy black race were separated from the white by indelible marks, and laws long before established, and were never thought of or spoken of except as property, and when the claims of the owner or the profit of the trader were supposed to need protection.
This state of public opinion had undergone no change when the Constitution was adopted, as is equally evident from its provisions and language."
The rest of the decision is a striking enumeration of the infinite ways in which Congress and the state legislatures had dehumanized and denied the most basic rights to blacks throughout the country, both North and South, and arguing that the more recent turn towards abolition in a few states could not overturn the basic original intent of the Constitution as an unapologetic upholding of white supremacy.
Don't read the critics of the Constitution for its worst indicters-- read its defenders like Taney. They are ultimately far more subversive to any respect for "original intent" or other worship of the Founders.
-- Nathan Newman