The Inquisition and the decline of science in Spain

A traditional argument that the Spanish Inquisition did not depress scientific research is that Spain experienced its Golden Age (1492–1657) after the Inquisition was formed (1478). Yet the arts, rather than the sciences, flourished; and we argue that the Inquisition had important chilling effects on the latter. Historically focused on persecuting suspected Jews, the Inquisition began refocusing its efforts on Protestantism, especially during the Council of Trent (1545–1563). The discovery of Protestant networks in two Spanish cities in 1557–58 helped fuel an abrupt increase in, and re-targeting of, inquisitorial activity. Scholars should have reacted by limiting their contacts and by exiting certain fields and institutions. To provide evidence for our account, we first document Spain’s decline in STEM fields, relative to the rest of Europe. We then provide the first systematic evidence on scholarly interactions among early modern Spanish book authors, documenting an immediate reduction in interactions after 1559, followed by a downward trend. We also document a significant reversal in a previously upward trend in affiliation with secular educational institutions. Since interacting with others working on similar problems is essential to progress in the sciences, our work helps explain the puzzling disjuncture between the glory of Spanish literary and visual arts during the Golden Age, on the one hand, and the poverty of its contributions to science, on the other.