To understand the vocation of the Catholic philosopher one must first answer the question, "what is philosophy?" Maritain in Introduction to Philosophy, said: “Philosophy is the science which by the natural light of reason studies the first causes or highest principles of all things -- is in other words, the science of things in their first causes, in so far as these belong to the natural order.”
The shocking term in the above definition is the word "science." Philosophy is a science, according to Maritain. Obviously there is a certain equivocation if one has already reduced the scope of knowledge to the realm of that which is strictly observable and quantifiable. Maritain follows the tradition of Aristotle according to which the term science designates certain knowledge of a thing through its causes. What are the causes? Is purpose a cause, is form a cause? You see one must philosophize to even define philosophy, let alone science.
Maritain thought that the reduction of the meaning of science derives from a prior decision, a prior attitude, to becomes masters and owners of nature. Maritain feared that the emphasis upon efficacy and pragmatism obscured the fundamental principles of philosophy.C. S. Lewis also pointed out in the Abolition of Man that "when we understand a thing analytically and then dominate and use it for our own convenience, we reduce it to the level of 'Nature' in the sense that we suspend our judgements of value about it, ignore its final cause (if any), and treat it in terms of quantity." This attitude is extended all the way to include human beings, now also reduced analytically to mere matter in motion, hence the Abolition of Man.
This is why Maritain’s philosophical efforts must begin with his notion of the intuition of being. We must be able to recognize and affirm the wholeness and integrity of reality in its being. Things are substances with various capacities to act and be acted upon. Form and finality are crucial to what they are and to our understanding of what they are. Once we can affirm the being of things, the reality of the world with an integrity deeper than our reductionist science, we can come to acquire the habit of philosophical thinking. about man, God and the world. Maritain entitled one of his books "The Range of Reason" in order to signify the full sweep of philosophical achievement as it encompasses an approach to God, the soul, justice, and truth.
Science will try to extrapolate from science to create fables and myths to answer these questions, inevitably arising from the deeper yearning for a true philosophical approach to the big issues. The ever-recurring temptation of science is the one first initiated so well by Lucretius – the poeticizing of the mechanisms of the world. Edward Wilson consciously invokes this same muse. The great questions of meaning about man, God and the world must lie beyond the scope of positive or empirical science. But science will make its poetic attempt, often doing bad theology rather than doing none at all. Also he criticizes the forms of contemporary philosophy because they bracket the question of being. As forms of epistemological idealism they trap the thinker within his own mind and never experience the relish of true being. The great vision of Christian renewal of temporal structures, the true activation of the temporal mission of the lay Christian, requires a preparation in the order of philosophy and spirituality. Maritain says that it will require “a great and patient work of revitalizing in the order of intelligence and the order of spirituality.”
Pope John Paul II defines philosophy in his encyclical letter Fides et Ratio (On the Relationship between Faith and Reason, 1999). Issued on the Feast Day of the Triumph of the Cross, the encyclical also criticizes the reductionism of modern thinking. The mystery of the cross plays a prominent role in the relationship between faith and reason – the cross is said to be a “reef” whose submerged mystery will either break up the relationship between faith and reason (actually he says that reason may come to grief on the shoals of its devising) or reason will be freed through the mystery of the cross to set forth upon a “boundless ocean of truth.” With such nautical metaphors, one thinks by way of contrast of both the timidity of a Locke and the temerity of a Nietzsche. Locke says at the outset of the Essay that we should avoid the "vast Ocean of Being" wherein a man has no sure footing; he recommends that the mind rest content with its short tether, because if the mind is not suited for metaphysical speculation, it is suited for practical matters -- "convenience" and "virtue" he says. Nietzsche on the other hand launches his hopes for the unbounded sea after the death of God. For John Paul, the cross represents the mystery of love, which cannot be eliminated and which provides the “ultimate answer” reasons seeks. Neither Locke nor Nietzsche would be characterized as philosophers of love. Jacques Maritain, on the other hand, was often characterized thusly. He saw fit to include a text of Raissa in The Peasant of the Garonne, “The True Face of God, or Love and Law.” Thus the last line of his book is Raissa’s -- “Love creates trust.” So much for the myth of the bitter old man’s last testimony. Maritain was a philosopher who lived in the mystery of the cross. Maritain’s was a Christian philosophy, a "philosophical speculation conceived in dynamic union with faith" (#76). The debates about the meaning, coherence and desirability of Christian philosophy were a matter of much debate a generation ago. The Pope’s encyclical provides a new stimulation for revisiting those debates.
Pope John Paul II commends specific thinkers by name as examples of the proper relationship between faith and reason, Edith Stein, John Henry Cardinal Newman, Etienne Gilson, and Jacques Maritain. They exhibited the “indispensable requirements” for an authentic philosophy “consonant with the Word of God” (§80-84). The first thing that philosophy must do is "recover its sapiential dimension as a search for the ultimate and overarching meaning of life ...... this sapiential dimension is all the more necessary today, because the immense expansion of humanity's technical capability demands a renewed and sharpened sense of ultimate values" (ibid.) This leads to the second requirement, viz., "that philosophy verify the human capacity to know the truth, to come to a knowledge which can reach objective truth by means of that adaequatio rei et intellectus to which the Scholastic Doctors referred .”(#82). The first two requirements entail a third: "the need for a philosophy of genuinely metaphysical range, capable, that is, of transcending empirical data in order to attain something absolute, ultimate and foundational in its search for truth." (#83) These three themes mark the work and achievement of Jacques Maritain, from beginning to end. They are the great themes of the work of any philosophy worthy of the name.