How can we think about people and cultures unlike our own? In the early modern period, the fact of human diversity presented Europeans with little cause for anxiety: they simply assumed the superiority of the West. During the 18th century this view was gradually abandoned, as thinkers argued that other peoples possessed reason and sensibility, and thus deserved the same respect that Westerners accorded themselves. Since that time, however, Enlightenment belief in the universalities of human nature has fallen into disrepute; critics allege that such notions have had disastrous consequences in the 20th century, ranging from prejudice to persecution and outright genocide.