48 The "good fight" (80) in the cause of the Faith is fought not only in the secrecy of the individual conscience or in the privacy of the home, but also in public life in all of its forms. In all the different parts of the world there exist nowadays problems of various kinds. There is no solution to these problems in exclusively human advice nor in principles which are often in contrast with the precepts of Christian law. Several mission countries are now "undergoing such speedy changes in social, economic, and political life that their entire future appears to depend on the outcome of those changes." (81) Indeed, problems which some countries have already solved or are solving with the help of their experience and traditions, are urgently in need of solution in other countries. There the problems are beset by serious dangers, inasmuch as they could be approached with deplorable levity, by resorting to certain doctrines which disregard, or even oppose, the religious values of individuals and nations. In order to safeguard both their private interests and those of the Church, Catholics must not ignore such problems, or wait until they are given the wrong solutions, which would thereafter require a much greater expenditure of energy in order to correct them and would place further obstacles in the path of the propagation of the Christian religious in the world.
Source: Princeps Pastorum (Vatican.va)