It's true many western enlightenment thinkers wrote wholeheartedly against slavery. However, they rarely, if ever, were actually referring to the actual slaves

It's true many western enlightenment thinkers wrote wholeheartedly against slavery. However, they rarely, if ever, were actually referring to the actual slaves in their midst. Instead most of the intellectual discourse surrounding slavery concentrated on rights for those who could vote (often a small section of the population). Was European morality at work when Leopold II destroyed half the population of Congo?