Pacem in Terris §90

⁹⁰ Truth further demands an attitude of unruffled impartiality in the use of the many aids to the promotion and spread of mutual understanding between nations which modern scientific progress has made available. This does not mean that people should be prevented from drawing particular attention to the virtues of their own way of life, but it does mean the utter rejection of ways of disseminating information which violate the principles of truth and justice, and injure the reputation of another nation. (55)