Positivism, not just an "ivory tower" philosophy, was a major force in the social, political, and educational life of Mexico during the last half of the nineteenth century. Once colonial conservatism had been conquered, the French Intervention ended, and Maximilian of Hapsburg executed, reformers wanted to create a new national order to replace the Spanish colonial one. The victorious liberals strove to achieve "mental emancipation," a kind of second independence, which would abolish the habits and customs imposed on Mexicans by three centuries of colonialism.

At this singular moment...