Fruitful dialogue between faith and reason cannot but render the work of charity more effective within society, and it constitutes the most appropriate framework for promoting fraternal collaboration between believers and non-believers in their shared commitment to working for justice and the peace of the human family. In the Pastoral Constitution Gaudium et Spes, the Council fathers asserted that “believers and unbelievers agree almost unanimously that all things on earth should be ordered towards man as to their centre and summit.” For believers, the world derives neither from blind chance nor from strict necessity, but from God’s plan. This is what gives rise to the duty of believers to unite their efforts with those of all men and women of good will, with the followers of other religions and with non-believers, so that this world of ours may effectively correspond to the divine plan: living as a family under the Creator’s watchful eye. A particular manifestation of charity and a guiding criterion for fraternal cooperation between believers and non-believers is undoubtedly the principle of subsidiarity, an expression of inalienable human freedom. Subsidiarity is first and foremost a form of assistance to the human person via the autonomy of intermediate bodies. Such assistance is offered when individuals or groups are unable to accomplish something on their own, and it is always designed to achieve their emancipation, because it fosters freedom and participation through assumption of responsibility. Subsidiarity respects personal dignity by recognizing in the person a subject who is always capable of giving something to others. By considering reciprocity as the heart of what it is to be a human being, subsidiarity is the most effective antidote against any form of all-encompassing welfare state. It is able to take account both of the manifold articulation of plans — and therefore of the plurality of subjects — as well as the coordination of those plans. Hence the principle of subsidiarity is particularly well-suited to managing globalization and directing it towards authentic human development. In order not to produce a dangerous universal power of a tyrannical nature, the governance of globalization must be marked by subsidiarity, articulated into several layers and involving different levels that can work together. Globalization certainly requires authority, insofar as it poses the problem of a global common good that needs to be pursued. This authority, however, must be organized in a subsidiary and stratified way, if it is not to infringe upon freedom and if it is to yield effective results in practice. – from Caritas in Veritate (2009)