More than 400 years ago, Michel de Montaigne of France invented a new literary tradition of close inward observation. “It is a thorny undertaking,” he writes, “to follow a movement so wandering as that of our mind.” Scholars, such as Sarah Bakewell, credit him with being the first to experiment with a type of essay that is restless and free flowing. She says that the two characteristics that distinguish Montaigne’s work from his contemporaries in the 1500s are “astonishment” and “fluidity.” Instead of recording his achievements, he wrote “to penetrate the opaque depths” of his mind as it flowed.
Bakewell, Sarah. How to Live -or- A Life of Montaigne in One Question and Twenty Attempts at an Answer. Other Press, 2010, p. 37.