Slavery is a wrong to each individual enslaved; and not merely to the first of a series. Natural law, therefore, as much forbids the enslaving of the child, as if the wrong of enslaving the parent had never been perpetrated.
The Complete Works of Lysander Spooner: The Unconstitutionality of Slavery, No Treason: The Constitution of No Authority, Vices are Not Crimes, Natural ... Laws of Congress, Prohibiting Private Mails