Historical figures can only be understood in the context of their time. This is occasionally used to explain why otherwise admirable people were racists, or sexists. The is a lot to like about Thomas Jefferson, yet he held slaves. This doesn’t diminish what he did for the United States, but it’s an unerasable stain on this founding father.
Others, who inhabited the same time and context, clearly saw slavery for what it was. Naturalist Alexander von Humboldt was one of them. He was the most famous scientist of his time and a decent man not only by the standards of his time, but by modern standards.
He insisted there were no superior or inferior human races. He condemned colonialism and slavery, and the degradation of nature that comes from its thoughtless exploitation. What, then, do we make of the fact that even in 1800, there were those who lived by modern moral standards? What does it say about the majority of their contemporaries who did not? Does it not suggest that the enlightened mind can perceive good and evil no matter the context?
The following are quotes from Andrea Wulf’s biography of Humboldt, The Invention of Nature.
On slavery:
Humboldt, though, never grew tired of condemning what he called ‘the greatest evil’ […] That the British, French or Spanish could argue, as they did, over who treated their slaves with greater humanity, Humboldt said, was as absurd as discussing ‘if it was more pleasant to have one’s stomach slashed open or be flayed.’
On colonialism:
The very idea of a colony, Humboldt argued, was an immoral concept and a colonial government was a ‘government of distrust’ […] Colonialism was disastrous for people and the environment; colonial society was based on inequality; the indigenous people were neither barbaric nor savages, and the colonists were as capable of scientific discoveries, art and craftsmanship as the Europeans.
Here is another book critical of colonialism from when it was in full swing.
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