It’s difficult to prove that oral and literate people think differently; orality, Havelock observed, doesn’t “fossilize” except through its nemesis, writing. But some supporting evidence came to hand in 1974, when Aleksandr R. Luria, a Soviet psychologist, published a study based on interviews conducted in the nineteen-thirties with illiterate and newly literate peasants in Uzbekistan and Kyrgyzstan. Luria found that illiterates had a “graphic-functional” way of thinking that seemed to vanish as they were schooled. In naming colors, for example, literate people said “dark blue” or “light yellow,” but illiterates used metaphorical names like “liver,” “peach,” “decayed teeth,” and “cotton in bloom.” Literates saw optical illusions; illiterates sometimes didn’t. Experimenters showed peasants drawings of a hammer, a saw, an axe, and a log and then asked them to choose the three items that were similar. Illiterates resisted, saying that all the items were useful.