242 As We have noted already, modern man has greatly deepened and extended his knowledge of nature's laws, and has harnessed the forces of nature, making them subservient to his ends. The magnitude of his achievements deserves ungrudging admiration; nor is he yet at the end of his resources. Nevertheless, in his striving to master and transform the world around him he is in danger of forgetting and of destroying himself. As Our Predecessor, Pope Pius Xl, lamented in Quadragesimo Anno: "And so bodily labor, which even after original sin was decreed by Providence for the good of man's body and soul, is in many instances changed into an instrument of perversion; for from the factory dead matter goes out improved, whereas men there are corrupted and degraded." (48)
Source: Mater et Magistra (Vatican.va)