From John XXIII’s encyclical Ad Petri Cathedram, of June 29, 1959:
Petrograd, July 4, 1917. Street demonstration on Nevsky Prospekt just after troops of the Provisional Government have opened fire with machine guns.
“The harmonious unity which must be sought among peoples and nations also needs ever greater improvement among the various classes of individuals. Otherwise mutual antagonism and conflict can result, as we have already seen. And the next step brings rioting mobs, wanton destruction of property, and sometimes even bloodshed. Meanwhile public and private resources diminish and are stretched to the danger point….
“Anyone, therefore, who ventures to deny that there are differences among social classes contradicts the very laws of nature. Indeed, whoever opposes peaceful and necessary cooperation among the social classes is attempting, beyond doubt, to disrupt and divide human society; he menaces and does serious injury to private interests and the public welfare….
The Bolshevik by Boris Mikhailovich Kustodiev
“The various classes of society, as well as groups of individuals, may certainly protect their rights, provided this is done by legal means, not violence, and provided that they do no injustice to the inviolable rights of others. All men are brothers. Their differences, therefore, must be settled by friendly agreement, with brotherly love for one another.”
Plinio Corrêa de Oliveira, Nobility and Analogous Traditional Elites in the Allocutions of Pius XII: A Theme Illuminating American Social History (York, Penn.: The American Society for the Defense of Tradition, Family, and Property, 1993), Documents V, p. 486.
