Catechism of the Catholic Church §1897 — excerpt
"Human society can be neither well-ordered nor prosperous unless it has some people invested with legitimate authority to preserve its institutions and to devote themselves as far as is necessary to work and care for the good of all."
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.
Also cites: John XXIII, PT 46