Thomas Aquinas: Whether God can be known in this life by natural reason?

Whether God can be known in this life

by natural reason?

P(1)-Q(12)-A(12) -O(1) — It seems that by natural reason we cannot

know God in this life. For Boethius says (De Consol. v) that “reason does

not grasp simple form.” But God is a supremely simple form, as was

shown above (Q(3), A(7)). Therefore natural reason cannot attain to know

Him.

P(1)-Q(12)-A(12) -O(2) — Further, the soul understands nothing by

natural reason without the use of the imagination. But we cannot have an

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imagination of God, Who is incorporeal. Therefore we cannot know God

by natural knowledge.

P(1)-Q(12)-A(12) -O(3) — Further, the knowledge of natural reason

belongs to both good and evil, inasmuch as they have a common nature.

But the knowledge of God belongs only to the good; for Augustine says

(De Trin. i): “The weak eye of the human mind is not fixed on that

excellent light unless purified by the justice of faith.” Therefore God

cannot be known by natural reason.

P(1)-Q(12)-A(12) — On the contrary, It is written (<450119>Romans 1:19),

“That which is known of God,” namely, what can be known of God by

natural reason, “is manifest in them.”

I answer that, 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 see the essence of God; because the

sensible effects of God do not equal the power of God as their cause.

Hence from the knowledge of sensible things the whole power of God

cannot be known; nor therefore 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 caused by Him.

Hence we know that His relationship with creatures so far as to be the

cause of them all; also that creatures differ from Him, inasmuch as He is

not in any way part of what is caused by Him; and that creatures are not

removed from Him by reason of any defect on His part, but because He

superexceeds them all.

P(1)-Q(12)-A(12) -RO(1) — Reason cannot reach up to simple form, so

as to know “what it is”; but it can know “whether it is.”

P(1)-Q(12)-A(12) -RO(2) — God is known by natural knowledge through

the images of His effects.

P(1)-Q(12)-A(12) -RO(3) — As the knowledge of God’s essence is by

grace, it belongs only to the good; but the knowledge of Him by natural

reason can belong to both good and bad; and hence Augustine says

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(Retract. i), retracting what he had said before: “I do not approve what I

said in prayer, ‘God who willest that only the pure should know truth.’

For it can be answered that many who are not pure can know many

truths,” i.e. by natural reason.