18 Besides requiring freedom, integral human development as a vocation also demands respect for its truth . The vocation to progress drives us to “do more, know more and have more in order to be more” . But herein lies the problem: what does it mean “to be more”? Paul VI answers the question by indicating the essential quality of “authentic” development: it must be “integral, that is, it has to promote the good of every man and of the whole man” . Amid the various competing anthropological visions put forward in today's society, even more so than in Paul VI's time, the Christian vision has the particular characteristic of asserting and justifying the unconditional value of the human person and the meaning of his growth. The Christian vocation to development helps to promote the advancement of all men and of the whole man. As Paul VI wrote: “What we hold important is man, each man and each group of men, and we even include the whole of humanity” . In promoting development, the Christian faith does not rely on privilege or positions of power, nor even on the merits of Christians (even though these existed and continue to exist alongside their natural limitations) , but only on Christ, to whom every authentic vocation to integral human development must be directed. The Gospel is fundamental for development , because in the Gospel, Christ, “in the very revelation of the mystery of the Father and of his love, fully reveals humanity to itself” . Taught by her Lord, the Church examines the signs of the times and interprets them, offering the world “what she possesses as her characteristic attribute: a global vision of man and of the human race” . Precisely because God gives a resounding “yes” to man , man cannot fail to open himself to the divine vocation to pursue his own development. The truth of development consists in its completeness: if it does not involve the whole man and every man, it is not true development. This is the central message of Populorum Progressio , valid for today and for all time. Integral human development on the natural plane, as a response to a vocation from God the Creator , demands self-fulfilment in a “transcendent humanism which gives [to man] his greatest possible perfection: this is the highest goal of personal development” . The Christian vocation to this development therefore applies to both the natural plane and the supernatural plane; which is why, “when God is eclipsed, our ability to recognize the natural order, purpose and the ‘good' begins to wane” .
Source: Caritas in Veritate (Vatican.va)