Abstract
In the history of European philosophy and science, René Descartes is considered an author of a methodology of radical doubt, meditation, and the conception that explains the cause of human errors. But the course on internalization, knowledge of one's own Self, methodology of searching foundation of knowledge and conception of perfect reason have been formed already in the times of a Late Antiquity, particular by Augustine in his works “Soliloquies” and “Confession”, Boethius’s “The Consolation of Philosophy” and was continued in the New age by Loyola’s “Spiritual exercises” and Teresa of Avila’s “The Interior Castle”. Therefore, Descartes could be rightfully considered rather the brilliant inheritor of this tradition than pioneer. To this chain of philosophers and theologians who were forerunners of Descartes’s theory of Radical doubt and especially problem of the source of human errors worth to add a new name – Hadewijch, the representative of medieval Dutch vernacular theology and her works “Visions” along with “Letters”. Precisely her point of view on cause of human errors, very close to the explanation have been given by Descartes in his IV Meditation. The aim of the research is to demonstrate common positions of Descartes’s and Hadewijch’s explanation of the nature of the errors.