Nineteenth-century racial science measured intelligence by skull size and diameter

Evidence

Le Bon’s work as a popular social scientist and Orientalist addressed two major issues: how to account for the difference between advanced and backward societies, and how to account for the difference within a society between the mass of its people and the elite. He had contributed in his early work to the new literature on intelligence, as the variable most closely correlated to the level of advancement of a race. Intelligence was measured by the volume and diameter of the skull, which were shown to increase as the brain itself evolved in size and complexity. (These findings of Le Bon were used by Durkheim, in his early work on The Division of Labour in Society.) Le Bon claimed to be the inventor of the pocket cephalometer, a caliper device with which a traveller could record the size of a people’s heads, and thereby calibrate the degree of their advancement. By this criterion, the black, yellow, and Caucasian races were clearly distinguishable as three separate stages on the ladder of evolution. — Timothy Mitchell, Colonising Egypt, 395

Categorization

• XREF: Connects to the broader history of scientific racism and the measuring of human difference that Mitchell later critiques; also connects to Durkheim’s early reliance on such data.
• SEED: Angle: the pocket cephalometer as a portable instrument of empire — how a traveller’s gadget encoded racial hierarchy and normalized it as ‘calibration’.