Fair for Its Day: Though violently disgusted by the cannibals, Crusoe ultimately decides against an offensive attack using arguments surprisingly close to modern cultural relativism. He also points out that Europeans (namely, the Spanish) are guilty of many atrocities in the New World themselves. When he finally does attack the cannibals, it's specifically to save people's lives.
I debated this very often with myself thus: "How do I know what God Himself judges in this particular case? It is certain these people do not commit this as a crime; it is not against their own consciences reproving, or their light reproaching them; they do not know it to be an offence, and then commit it in defiance of divine justice, as we do in almost all the sins we commit. They think it no more a crime to kill a captive taken in war than we do to kill an ox; or to eat human flesh than we do to eat mutton."
- Also seen in the book's depiction of Friday. It was common in this era for indigenous peoples to be portrayed as simply brute savages (think Shakespeare's Caliban). But Friday is never anything but kind, brave, loyal, handsome, and intelligent - the exact opposite of what you would call savage. He may still be Crusoe's inferior, but he's also an extremely likeable character.