SECOND ARTICLE [I, Q. 86, Art. 2]

Whether Our Intellect Can Know the Infinite?

Objection 1: It would seem that our intellect can know the infinite.

For God excels all infinite things. But our intellect can know God,

as we have said above (Q. 12, A. 1). Much more, therefore, can our

intellect know all other infinite things.

Obj. 2: Further, our intellect can naturally know genera and

species. But there is an infinity of species in some genera, as in

number, proportion, and figure. Therefore our intellect can know

the infinite.

Obj. 3: Further, if one body can coexist with another in the same

place, there is nothing to prevent an infinite number of bodies being

in one place. But one intelligible species can exist with another in

the same intellect, for many things can be habitually known at the

same time. Therefore our intellect can have an habitual knowledge of

an infinite number of things.

Obj. 4: Further, as the intellect is not a corporeal faculty, as we

have said (Q. 76, A. 1), it appears to be an infinite power. But an

infinite power has a capacity for an infinite object. Therefore our

intellect can know the infinite.

_On the contrary,_ It is said (Phys. i, 4) that "the infinite,

considered as such, is unknown."

_I answer that,_ Since a faculty and its object are proportional to

each other, the intellect must be related to the infinite, as is its

object, which is the quiddity of a material thing. Now in material

things the infinite does not exist actually, but only potentially, in

the sense of one succeeding another, as is said Phys. iii, 6.

Therefore infinity is potentially in our mind through its considering

successively one thing after another: because never does our

intellect understand so many things, that it cannot understand more.

On the other hand, our intellect cannot understand the infinite

either actually or habitually. Not actually, for our intellect cannot

know actually at the same time, except what it knows through one

species. But the infinite is not represented by one species, for if

it were it would be something whole and complete. Consequently it

cannot be understood except by a successive consideration of one part

after another, as is clear from its definition (Phys. iii, 6): for

the infinite is that "from which, however much we may take, there

always remains something to be taken." Thus the infinite could not be

known actually, unless all its parts were counted: which is

impossible.

For the same reason we cannot have habitual knowledge of the infinite:

because in us habitual knowledge results from actual consideration:

since by understanding we acquire knowledge, as is said _Ethic._ ii, 1.

Wherefore it would not be possible for us to have a habit of an

infinity of things distinctly known, unless we had already considered

the entire infinity thereof, counting them according to the succession

of our knowledge: which is impossible. And therefore neither actually

nor habitually can our intellect know the infinite, but only

potentially as explained above.

Reply Obj. 1: As we have said above (Q. 7, A. 1), God is called

infinite, because He is a form unlimited by matter; whereas in

material things, the term "infinite" is applied to that which is

deprived of any formal term. And form being known in itself, whereas

matter cannot be known without form, it follows that the material

infinite is in itself unknowable. But the formal infinite, God, is

of Himself known; but He is unknown to us by reason of our feeble

intellect, which in its present state has a natural aptitude for

material objects only. Therefore we cannot know God in our present

life except through material effects. In the future life this defect

of intellect will be removed by the state of glory, when we shall be

able to see the Essence of God Himself, but without being able to

comprehend Him.

Reply Obj. 2: The nature of our mind is to know species abstracted

from phantasms; therefore it cannot know actually or habitually

species of numbers or figures that are not in the imagination, except

in a general way and in their universal principles; and this is to

know them potentially and confusedly.

Reply Obj. 3: If two or more bodies were in the same place, there

would be no need for them to occupy the place successively, in order

for the things placed to be counted according to this succession of

occupation. On the other hand, the intelligible species enter into

our intellect successively; since many things cannot be actually

understood at the same time: and therefore there must be a definite

and not an infinite number of species in our intellect.

Reply Obj. 4: As our intellect is infinite in power, so does it know

the infinite. For its power is indeed infinite inasmuch as it is not

terminated by corporeal matter. Moreover it can know the universal,

which is abstracted from individual matter, and which consequently is

not limited to one individual, but, considered in itself, extends to

an infinite number of individuals.

_______________________

Summa Theologica, Part I (Prima Pars) From the Complete American Edition · 第 538 / 722 题