Edit: To be precise, to a major extent, the causality is probably in the opposite direction—because treating people the way slaves were treated is wrong, those with a stake in the matter had it widely argued that the chattel slaves were not people in the proper sense of the word.
A fair point, to be sure.
Edit: To be precise, to a major extent, the causality is probably in the opposite direction—because treating people the way slaves were treated is wrong, those with a stake in the matter had it widely argued that the chattel slaves were not people in the proper sense of the word.