Was the US Constitution more pro-slavery or anti-slavery in its original framework?

What will be said of this new principle of founding a Right to govern Freemen on a power derived from Slaves[?] …The omitting the Word will be regarded as an Endeavour to conceal a principle of which we are ashamed.  —John Dickinson, July 9, 1787

For more details, see these resource pages from the Knowledge for Freedom seminar:



 Article 1, Section 2

Representatives and direct taxes shall be apportioned among several States which may be included within this Union, according to their respective numbers, which shall be determined by adding to the whole number of free persons, including those bound to service for a term of years, and excluding Indians not taxed, three-fifths of all other persons.


Article 1, Section 9

The Migration or Importation of such Persons as any of the States now existing shall think proper to admit, shall not be prohibited by the Congress prior to the Year one thousand eight hundred and eight, but a Tax or duty may be imposed on such importation, not exceeding ten dollars for each Person.


Article 4, Section 2

No Person held to Service or Labour in one State, under the Laws thereof, escaping into another, shall, in Consequence of any Law or Regulation therein, be discharged from such Service or Labour, but shall be delivered up on Claim of the Party to whom such Service or Labour may be due.


There shall be neither slavery nor involuntary servitude in the said territory, otherwise than in the punishment of crimes whereof the party shall have been duly convicted….”

–Article VI, Northwest Ordinance, July 13, 1787


“Every master of slaves is born a petty tyrant.  They bring the judgment of heaven upon a Country. As nations can not be rewarded or punished in the next world they must be in this.  By an inevitable chain of causes & effects providence punishes national sins, by national calamities.”

–George Mason, August 22, 1787

Memory & Meaning