In a famous passage from his treaty on logic (La logique, ou le premiers développements de l’art de penser, 1780), French philosopher Étienne Bonnot de Condillac invented a story to help his readers understand his very idea of the unity of the perceiving soul. “I suppose,” he wrote, “a castle that commands a vast and luxuriant plain […] We arrive in this castle at night. The next morning the windows are thrown open, just when the sun begins to gild the horizon; we have caught a glimpse of the prospect, and the windows are immediately closed. […] That first glance is not sufficient to give us a complete knowledge of that plain […] It is for this reason that when the windows were shut again, none of us would have been able to give an account of what he had seen. This is the way in which we look at many things but learn nothing.”

The idea of simultaneous sensations, and of their limits within the boundaries of human psychology, constitutes a particularly lively field of debates in scientific and artistic circles between the end of the nineteenth and the beginning of the twentieth century. Professor Maria Elena Versai‘s essay retraces the impact that those debates had on the birth of abstract art, and shows how artists such as Robert Delaunay, Umberto Boccioni and Giacomo Balla contributed to establishing modern painting not just as a form of visual experimentation, but as a radically new mode of reflection on the process of seeing, perceiving, and making sense of the world.