236. There are three stages which should normally be followed in the reduction of social principles into practice. First, one reviews the concrete situation; secondly, one forms a judgment on it in the light of these same principles; thirdly, one decides what in the circumstances can and should be done to implement these principles. These are the three stages that are usually expressed in the three terms: look, judge, act.
237. It is important for our young people to grasp this method and to practice it. Knowledge acquired in this way does not remain merely abstract, but is seen as something that must be translated into action.
John XXIII, Mater et Magistra, 1961