“Take the Pickaxe of Your Understanding and Dig!”

Abstract In the late Middle Ages, Christine de Pizan contributed decisively to the development of Renaissance humanist ideas, which later resulted in the principle of the Enlightenment. In The Book of the City of Ladies, she laid the foundation for establishing a self-determined way of thinking that did not rely on authorities in the search for truth, but on the individual mind and one’s own experience as primary sources of knowledge—she urged people to have the courage to use their own senses. This now famous appeal is mainly and primarily associated with Kant and the Enlightenment, although de Pizan had already formulated a similar postulate 380 years earlier. The study of de Pizan also provides evidence that ideas of (early) female thinkers are partly integrated into the (philosophical) work of later male thinkers and sold as their own sole intellectual property. Only by determining the role of women in (philosophical) history do such facts become clear.