Thomistic Philosophy Page
[ Topics | Questions | Bibliography | Links | Bookstore ]
Commentary on the First Book of the Sentences of Peter
Lombard, Distinction III, Question 1, Article 2
Whether the existence of God (Deum esse) is per se notum
To the second article we thus proceed.
- It seems that the existence of God (Deum esse) is
per se notum (known intuitively or through itself). For that
is called per se notum the knowledge of which is places in us,
e.g. that every whole is greater than its part. But knowledge of God's
existence, according to John Damascene, Orthodox Faith, Book
I, ch. 1, naturally is inserted in everything. Therefore, the existence of
God is per se notum.
- Again, just as sensible light is related to sight, so intelligible light
is related to the intellect. But sensible light is of itself visible; that
is, nothing is seen except through the mediation of it. Therefore, God is
known of Himself, without mediation.
- Again, all knowledge comes about through the union of the thing known
with the knower. But God is through Himself inwardly present to the soul,
even more so than the soul is to itself. Therefore, He can be known through
- Furthermore, that is per se notum which cannot be thought
not to be. But God cannot be thought not to be. Therefore, His existence
is per se notum. The proof of the middle (of the argument) is
made by Anselm in Proslogion, Ch. 15: God is that than which
a greater cannot be thought. But that which cannot be thought not to be is
greater than that which can be thought not to be. Therefore, God cannot be
thought not to be. It (the middle) can be proved in another way: No thing
can be known without (understanding) its quiddity (whatness), as man (cannot
be known) without (understanding) that he is a mortal rational animal. But
the quiddity of God is His very existence, as Avicenna says, On
Intelligences, Ch. 1. Therefore, God cannot be thought not to be.
On the contrary.
- Those things that are per se nota as the Philosopher says
in Metaphysics, Book IV, even though they may be denied
exteriorly by the mouth, can never be denied interiorly in the heart. But
the existence of God can be denied in the heart; Psalm 13, 1 "The fool has
said in his heart: There is no God." Therefore, the existence of God is not
per se notum.
- Again, whatever is the conclusion of a demonstration is not per se
notum. But the existence of God is demonstrated even by
philosophers (cf. Physics VII and Metaphysics
XII). Therefore, the existence of God is not per se notum.
I respond that one can speak about the knowledge of something in two
ways, either according to the thing itself or with reference to us
(quoad nos). Therefore, speaking about God according to
Himself, His existence is per se notum and He Himself is
understood through Himself (per se intellectus) and not
through the fact that we make Him intelligible as we make material things
intelligible in act.
Speaking about God with respect to us, this again can be considered in
two ways. On the one hand, according to His likeness and participation;
and in this way His existence is per se notum. For nothing
is known except through its truth which is modelled (exemplata)
on God. However, that there is truth is per se notum. On
the other hand, according to a supposit, that is, considering God Himself
according to what is in His nature something incorporeal. And in this way,
it (the existence of God) is not per se notum. Indeed, many
are found to deny that God exists, as all philosophers who do not posit an
Agent Cause, e.g. Democritus and certain others (Metaphysics,
Book I). And the reason for this is that those things that are per se
notum are made known immediately through sense, just as, by seeing
a whole and a part, we immediately know that every whole is greater than
its part without any investigation. Wherefore, the Philosopher says in
Posterior Analytics, Book I, "We know (first) principles when
we know (their) terms." But by sensible sight we cannot come upon God
except by proceeding as follows: these things are caused, and everything
which is caused is from some agent cause; the First Agent Cause cannot be
a body. And so we do not come upon God except by arguing; and no such
(procedure) is per se notum. And this is the rationale of
Avicenna in On Intelligences, Ch. 1.
Replies to objections.
- The authority of John Damascene should be understood to concern divine
knowledge that is placed in us according to the likeness of Him (God) and
not according to what is in His nature, just as it is even said that all
things desire God, not, indeed, (that they desire) Him as He is considered
in His nature, but in a likeness to Him. For, nothing is desired except
insofar as it has His likeness; and so nothing is known (except insofar as
it has His likeness).
- Our sight is proportioned to seeing corporeal light through itself
alone; but our intellect is not proportioned to knowing something by a
natural knowledge except through sensible things. And so it cannot come
upon a purely intelligible thing except through argumentation.
- Although God is in the soul through (His) essence, presence and power,
nevertheless, He is not in it as the object of the intellect; and this is
required for knowledge. Wherefore, even the soul is itself present to
itself. Nevertheless, it is most difficult (to come) to knowledge of the
soul, nor is it (knowledge of the soul) found in it (the soul) except by
reasoning from objects to acts, and from acts to the power.
- The reasoning of Anselm should be understood thus: After we understand
(intelligimus) God, it cannot be understood
(intelligi) that there is a God and (at the same time)
He be able to be thought (cogitari) not to be. But,
nevertheless, from this (fact) it does not follow that someone would not be
able to deny (His existence) or think that God does not exist. For one can
think that there is nothing of the sort than which a greater cannot be
thought. And so his (Anselm's) reasoning proceeds from this supposition,
that it be supposed that there is something than which a greater cannot be
One should answer in a similar way to the other proof.
Return to the Aquinas on the Existence of God