The article deals with a little-studied aspect of the relationship between Medieval and Renaissanceworldviews, which coexisted in the XIV‑XVI centuries in the Christian West. Medieval consciousness was based on the idea of the "senility of the world" and its near death, the moral, intellectual and physical degradation of mankind. Such idea was contrary to anthropology and historical optimism of humanists. Theyput forwardthe idea of the inexhaustible power of nature, which was capable in the present and in the future to produce prominent persons who were not inferior to the "ancients" in intellectual and moral terms.The world, humanists believed, had not aged, and its end would take place in the distant and uncertain future.
Key words: Renaissance, Reformation, Middle Ages, humanism, “senility of the world”, “end of the world”.