72 Technical expertise is necessary, but it must be accompanied by concrete signs of genuine love. Untainted by overbearing nationalistic pride or any trace of racial discrimination, experts should learn how to work in collaboration with everyone. They must realize that their expert knowledge does not give them superiority in every sphere of life. The culture which shaped their living habits does contain certain universal human elements; but it cannot be regarded as the only culture, nor can it regard other cultures with haughty disdain. If it is introduced into foreign lands, it must undergo adaptation. Thus those who undertake such work must realize they are guests in a foreign land; they must see to it that they studiously observe its historical traditions, its rich culture, and its peculiar genius. A rapprochement between cultures will thus take place, bringing benefits to both sides.
Source: Populorum Progressio (Vatican.va)