Firmissimam Constantiam §15

¹⁵ Thus, while saving the essence of the primary and fundamental rights, such as the right of ownership, remember that at times the common good imposes restrictions on such rights as a recourse more frequent than in the past to the applications of social justice. As a protection for the dignity of the human being, it may be necessary at times to denounce and to blame boldly unjust and unworthy living conditions; at the same time, however, care must be taken to guard against either making violence legitimate with the pretext of applying a remedy to the ills of the people, or admitting and favoring those rapid and violent changes of temporal conditions of society which may lead to effects that are more harmful than the evil itself which is intended to be corrected.