After Rosling spent a day spent asking villagers in the remotest part of Africa about nutrition, the villagers cooked Rosling and his associate a grand dinner consisting of rat. For dessert, Rosling was served lightly fried larvae that appeared to be moving. Rosling’s associate, who was from Denmark, ate them without complaint. Unable to stomach the thought of eating the larvae, Rosling lied on the spot about how people from Denmark ate larvae but people from Sweden did not because it was against their culture. To prove his point, he showed on a map how the countries were divided by water, and the villagers happily ate the larvae for him. Rosling placed himself in one category (Swedish—unable to eat larvae) and his associate in another (Danish—able to eat larvae).

The human brain naturally categorizes and generalizes everything. This universal trait allowed Rosling to convince the villagers of a false difference between people from Denmark and Sweden. Categories “give structure to our thoughts” (146). Without categories, we would lack frameworks for ideas as well as ways to compare ideas. Generalization becomes a problem when it makes us group dissimilar things together or assume that every person/thing in a certain group is identical.