13. Reason’s power to know God
13. REASON’S POWER TO KNOW GOD
If we can know God by reason, why do we need faith and revelation? If we can’t know God by reason, how can faith be intelligent and intelligible? What is the role of reason in our faith life?
Whether God can be known in this life by natural reason?
It is written (Rom 1:19), That which is known of God . . . is manifest in them . . .
Our natural knowledge begins from sense. Hence our natural knowledge can go as far as it can be led by sensible things. But our mind cannot be led by sense so far as to know the essence of God because the sensible effects of God do not equal the power of God as their cause. Hence from sensible things the whole power of God cannot be known, nor . . . can His essence be seen.
But because they are His effects and depend on their cause, we can be led from them so far as to know of God whether He exists and to know of Him what must necessarily belong to Him as the first cause of all things, exceeding all things created by Him. Hence we know His relationship with creatures so far as to be the cause of them all; also that . . . He superexceeds them all (I,12,12).
We can know by faith as well as reason that we can know God by reason as well as faith. The Bible (Rom 1-2) and the Church (Vatican Council I) clearly tell us that everyone, even unbelievers, can know that there is a God by nature (“sensible things”) and by conscience. If there is design, there is a Designer; and if there is a moral law, there is a moral Lawgiver. Reason can lead us that far—to a Mind behind nature and a Will behind the moral law—though it cannot tell us the essence of this Being.
So our own reason, if honestly and commonsensically followed, will do two things: it will begin our journey to God by assuring us that there is indeed a God at the end; and it will confess its inadequacy to finish the journey, and will send us looking for the higher vehicle that can finish it: for divine revelation, which gives us the road map, and for divine grace, which gives us the fuel.
At the end of the journey is total truth (the understanding of the ultimate reason for all things), total goodness (perfect holiness, and the model for all holiness), and total beatitude (infinite, unending, ecstatic, incomprehensible joy). If we honestly admit our need and desire for these three things at the beginning of the journey, we will eventually arrive at the end; that is a solemn promise from God himself: “All who seek [Me] will find (Me)” (Mt 7:7-11). Only those who are not honest with their own nature, and do not seek, will fail to come to know the divine nature; only those who refuse their own humanity will fail to reach the divinity; only those who suppress these three clues God has put into their deepest heart will find misery rather than happiness in their heart at the end.
How much can reason tell us about God? Enough to begin but not enough to end. St. Thomas lists three things about God that we can know by reason alone: (1) that He exists, (2) that He is the first cause and ultimate explanation of all things, of their existence as well as of their design and intelligibility; and (3) that He is mysterious to us not because He is less real, true, good, or beautiful than all His creatures, but more. He is to our mind as the sun is to the eyes of a bat or an owl.
Thus St. Thomas avoids the two opposite extremes of theological skepticism and rationalism, intellectual despair and intellectual pride. Like Aristotle, his habit is always to seek out and avoid two extremes on nearly every issue. For there is usually one angle for standing upright and two angles for falling, to the right or to the left.