God The Creator of the Cosmos - in more detail
The Existence of God
From the spiritual nature of man
Faith and reason are not opposed
God can be known with certainty from the created world
The need for revelation
The Existence of God
From the spiritual nature of man
The human person: With his openness to truth and beauty, his sense of moral goodness, his freedom and the voice of his conscience, with his longing for the infinite and for happiness, man questions himself about God’s existence. In all this he discerns signs of his spiritual soul. The soul, the "seed of eternity we bear in ourselves, irreducible to the merely material," can have its origin only in God. (32)God’s voice echoes in our conscience
Deep within his conscience man discovers a law which he has not laid upon himself but which he must obey. Its voice, ever calling him to love and to do what is good and to avoid evil, sounds in his heart at the right moment....For man has in his heart a law inscribed by God...His conscience is man’s most secret core and his sanctuary. There he is alone with God whose voice echoes in his depths. (1776)God - first cause and final end of all things
The world, and man, attest that they contain within themselves neither their first principle not their final end, but rather that they participate in Being itself, which alone is without origin or end. Thus, in different ways, man can come to know that there exists a reality which is the first cause and final end of all things, a reality, that "everyone calls ‘God’." (St Thomas Aqu STh I,2,3) (34)Religion and Science
Faith and reason are not opposed
Man’s faculties make him capable of coming to a knowledge of the existence of a personal God. But for man to be able to enter into real intimacy with him, God willed both to reveal himself to man, and to give him the grace of being able to welcome this revelation in faith. The proof of God’s existence, however, can predispose one to faith and help one to see that faith is not opposed to reason. (35)Faith and science
Though faith is above reason, there can never be any real discrepancy between faith and reason. Since the same God who reveals mysteries and infuses faith has bestowed the light of reason on the human mind, God cannot deny himself, nor can truth ever contradict truth. Consequently, methodical research in all branches of knowledge, provided it is carried out in a truly scientific manner and does not override moral laws, can never conflict with the faith, because the things of the world and the things of faith derive from the same God. The humble and persevering investigator of the secrets of nature is being led, as it were, by the hand of God in spite of himself, for it is God, the conserver of all things, who made them what they are. (159)The path from science to God
The question about the origins of the world and of man has been the object of many scientific studies which have splendidly enriched our knowledge of the age and dimensions of the cosmos, the development of life-forms and the appearance of man. These discoveries invite us to even greater admiration for the greatness of the Creator, prompting us to give him thanks for all his works and for the understanding and wisdom he gives to scholars and researchers. With Solomon we can say: "It is he who gave me unerring knowledge of what exists, to know the structure of the world and the activity of the elements...for wisdom, the fashioner of all things, taught me". (Wis 7:17-22)Knowledge of God According to the Church
God can be known with certainty from the created world
"Our holy mother, the Church, holds and teaches that God, the first principle and last end of all things, can be known with certainty from the created world by the natural light of human reason." (Vat I, Dei Filius) Without this capacity, man would not be able to welcome God’s revelation. Man has the capacity because his is created "in the image of God." (Gen 1:27) (36)Original sin and personal sin darken the mind to God
In the historical conditions in which he finds himself, however, man experiences many difficulties in coming to know God by the light of reason alone:"Though human reason is, strictly speaking, truly capable by its own natural power and light of attaining to a true and certain knowledge of the one personal God, who watches over and controls the world by his providence, and of the natural law written in our hearts by the Creator; yet there are many obstacles which prevent reason from the effective and fruitful use of this inborn faculty. For the truths that concern the relations between God and man wholly transcend the visible order of things, and if they are translated into human action and influence it, they call for self-surrender and abnegation. The human mind, in its turn, is hampered in the attaining of such truths, not only by the impact of the sense and the imagination, but also by disordered appetites which are the consequences of original sin. So it happens that men in such matters easily persuade themselves that what they would not like to be true is false or at least doubtful." (Pius XII, Humani Generis). (37)
The need for revelation
This is why man stands in need of being enlightened by God’s revelation, not only about those things that exceed his understanding, but also "about those religious and moral truths which themselves are not beyond the grasp of human reason, so that even in the present condition of the human race, they can be known by all men with ease, with certainty and with no admixture of error." (Pius XII, Humani Generis) (38)Knowledge of God from creation is necessary in dialogue with other religions, philosophers and scientists
In defending the ability of human reason to know God, the Church is expressing her confidence in the possibility of speaking about him to all men and with all men, and therefore of dialogue with other religions, with philosophy and science, as well as with unbelievers and atheists. (39)The goodness, truth, and beauty of creatures leads to God
Since our knowledge of God is limited, our language about him is equally so. We can name God only by taking creatures as our starting point, and in accordance with our limited human ways of knowing and thinking. (40)
All creatures bear a certain resemblance to God, most especially man, created in the image and likeness of God. The manifold perfections of creatures - their truth, their goodness, their beauty - all reflect the infinite perfection of God. Consequently we can name God by taking his creatures’ perfections as our starting point, "for from the greatness and beauty of created things comes a corresponding perception of their Creator." (Wis 13:5) (41)The Creator transcends all creatures
God transcends all creatures. We must therefore continually purify our language of everything in it that is limited, image-bound or imperfect, if we are not to confuse our image of God - the "inexpressible, the incomprehensible, the invisible, the ungraspable" - with our human representation. Our human words fall short of the mystery of God. (42)
In brief - When he listens to the message of creation and to the voice of conscience, man can arrive at certainty about the existence of God, the cause and the end of everything. (46)
The Church teaches that the one true God, our Creator and Lord, can be known with certainty from his works, by the natural light of human reason. (cf. Vat I, Can 2) (47)