23 But that harmful and deplorable passion for innovation which was aroused in the sixteenth century threw first of all into confusion the Christian religion, and next, by natural sequence, invaded the precincts of philosophy, whence it spread amongst all classes of society. From this source, as from a fountain-head, burst forth all those later tenets of unbridled license which, in the midst of the terrible unheavals of the last century, were wildly conceived and boldly proclaimed as the principles and foundation of that new conception of law which was not merely previously unknown, but was at variance on many points with not only the Christian, but even the natural law.
Source: Immortale Dei (Vatican.va)