from those of His effects
which are known to us.

Reply Obj. 1: The existence of God and other like truths about
God, which can be known by natural reason, are not articles of faith,
but are preambles to the articles; for faith presupposes natural
knowledge, even as grace presupposes nature, and perfection supposes
something that can be perfected. Nevertheless, there is nothing to
prevent a man, who cannot grasp a proof, accepting, as a matter of
faith, something which in itself is capable of being scientifically
known and demonstrated.

Reply Obj. 2: When the existence of a cause is demonstrated
from an effect, this effect takes the place of the definition of the
cause in proof of the cause's existence. This is especially the case
in regard to God, because, in order to prove the existence of
anything, it is necessary to accept as a middle term the meaning of
the word, and not its essence, for the question of its essence follows
on the question of its existence. Now the names given to God are
derived from His effects; consequently, in demonstrating the existence
of God from His effects, we may take for the middle term the meaning
of the word "God".

Reply Obj. 3: From effects not proportionate to the cause no
perfect knowledge of that cause can be obtained. Yet from every effect
the existence of the cause can be clearly demonstrated, and so we can
demonstrate the existence of God from His effects; though from them we
cannot perfectly know God as He is in His essence.
_______________________

THIRD ARTICLE [I, Q. 2, Art. 3]

Whether God Exists?

Objection 1: It seems that God does not exist; because if one of two
contraries be infinite, the other would be altogether destroyed. But
the word "God" means that He is infinite goodness. If, therefore, God
existed, there would be no evil discoverable; but there is evil in the
world. Therefore God does not exist.

Obj. 2: Further, it is superfluous to suppose that what can be
accounted for by a few principles has been produced by many. But it
seems that everything we see in the world can be accounted for by
other principles, supposing God did not exist. For all natural things
can be reduced to one principle which is nature; and all voluntary
things can be reduced to one principle which is human reason, or will.
Therefore there is no need to suppose God's existence.

_On the contrary,_ It is said in the person of God: "I am Who am." (Ex.
3:14)

_I answer that,_ The