"Sacred Scripture teaches the human family what the experience of the ages confirms: that while human progress is a great advantage to man, it brings with it a strong temptation. For when the order of values is jumbled and bad is mixed with the good, individuals and groups pay heed solely to their own interests, and not to those of others. Thus it happens that the world ceases to be a place of true brotherhood. In our own day, the magnified power of humanity threatens to destroy the race itself."