| Medieval Sourcebook:
On The Eternity of the World
(DE AETERNITATE MUNDI)
DE AETERNITATE MUNDI []
Translation © 1991, 1997 by Robert
Let us assume, in accordance with the Catholic faith, that the
world had a beginning in time. The question still arises whether
the world could have always existed, and to explain the truth
of this matter, we should first distinguish where we agree with
our opponents from where we disagree with them. If someone holds
that something besides God could have always existed, in the sense
that there could be something always existing and yet not made
by God, then we differ with him: such an abominable error is contrary
not only to the faith but also to the teachings of the philosophers,
who confess and prove that everything that in any way exists cannot
exist unless it be caused by him who supremely and most truly
has existence. However, someone may hold that there has always
existed something that, nevertheless, had been wholly caused by
God, and thus we ought to determine whether this position is tenable.
If it be impossible that something caused by God has always existed,
it will be so either because God could not make something that
has always existed or because such a thing could not be made,
regardless of God's ability to make it. [] As to the first, all parties agree that, in view of his
infinite power, God could have made something that has always
existed. [] It
remains to be seen, therefore, whether something that has always
existed can be made.
If such a thing cannot be made, the impossibility will arise for
one of two reasons: either because of an absence of a passive
potentiality or because of some contradiction between the ideas
involved. [] In
regard to the first, notice that before an angel is made, we may
say, in a certain manner of speaking, that the angel cannot be
made, [] since
no passive potentiality precedes its being, for an angel is not
made from pre-existing matter. Nevertheless, God was able to make
the angel, and he was able to cause the angel to be made, for
God made it, and it was made. Therefore, if we understand "being
made" or "being caused" as implying the pre-existence
of a passive potentiality, then it should to be conceded, according
to faith, that something caused cannot always exist, for it would
then follow that a passive potentiality has always existed, and
this is heretical. But since a passive potentiality need not precede
in time whatever God may make, it does not follow that God could
not have made something that has always existed.
In regard to the second, someone may hold that something that
has always existed cannot be made because such a thing is self-contradictory,
just as an affirmation and a denial cannot be made simultaneously
true. Still, some people say that God can even make self-contradictories
things, while others say God cannot make such things, for such
things are actually nothing. Clearly, God cannot make such things
come to be, for the assumption that such a thing exists immediately
refutes itself. Nevertheless, if we allow that God can make such
things come to be, the position is not heretical, though I believe
it is false, just as the proposition that the past did not occur
is false, about which Augustine says (XXVI Contra Faustum cap. 5), "Anyone who says, 'If God is omnipotent, let him
make what has happened not to have happened,' does not realize
that he is saying, 'If God is omnipotent, let him make true things
false insofar as they are true.'" [PL 42, 481.] Nevertheless,
certain great men have piously maintained that God can make past
events not to have happened, and this was not reputed to be heretical.
We thus ought to determine whether there is any contradiction
between these two ideas, namely, to be made by God and to have
always existed. And, whatever may be the truth of this matter,
it will not be heretical to say that God can make something created
by him to have always existed, though I believe that if there
were a contradiction involved in asserting this, the assertion
would be false. However, if there is no contradiction involved,
then it is neither false nor impossible that God could have made
something that has always existed, and it will be an error to
say otherwise. For, if there is no contradiction, we ought to
admit that God could have made something that has always existed,
for it would be clearly derogatory to the divine omnipotence,
which exceeds every thought and power, to say that we creatures
can conceive of something that God is unable to make. (Nor are
sins an instance to the contrary, for, considered in themselves,
they are nothing.) In this, therefore, the entire question consists:
whether to be wholly created by God and not to have a beginning
in time are contradictory terms.
That they are not contradictory can be shown as follows. If they
are contradictory, this is for one or both of these two reasons:
either because the agent cause must precede the effect in time,
or because non-being must precede the effect in time, for we say
that what God creates comes to be out of nothing.
First, we should show that it is not necessary that an agent cause,
in this case God, precede in time that which he causes, if he
should so will. This can be shown in several ways. First, no cause
instantaneously producing its effect necessarily precedes the
effect in time. God, however, is a cause that produces effects
not through motion but instantaneously. Therefore, it is not necessary
that he precede his effects in time. The first premise is proved
inductively from all instantaneous changes, as, for example, with
illumination and other such things. But the premise may be proved
by reason as well.
For, at whatever instant a thing exists, at that instant it can
begin to act, as is clear in the case of all things that come
to be by generation: in the very instant at which there is fire,
the fire heats. But in an instantaneous action, the beginning
and the end of the action are simultaneous, indeed identical,
as is clear in the case of all indivisible things. Hence, at whatever
moment an agent instantaneously producing an effect exists, the
end of its action can exist as well. The end of the action, however,
is simultaneous with the thing made. Therefore, there is no contradiction
if we suppose that a cause instantaneously producing an effect
does not precede its effect in time. A contradiction does obtain
if the cause involved is one that produces its effects through
motion, for the beginning of the motion precedes in time the end
of the motion. Since people are accustomed to considering the
type of cause that produces effects through motion, they do not
easily grasp that an agent cause may fail to precede its effect
in time, and so, having limited experience, they easily make a
Nor can the conclusion be avoided by saying that God is an agent
cause that acts voluntarily, for neither the will nor the voluntary
agent need precede its effect in time, unless the agent cause
acts from deliberation, which we take to be absent in God.
Further, a cause that produces the whole substance of a thing
does not, in producing a whole substance, act in a less perfect
way than does a cause that produces just a form in producing the
form. On the contrary, it acts in a much more perfect way, since
it does not act by educing from the potentiality of matter, as
do causes that merely produce forms. However, some causes that
produce just forms are such that, whenever the cause exists, the
form produced by it exists as well, as is clear in the case of
illumination by the sun. Therefore, much more can God, who produces
the whole substance of things, make something caused by him exist
whenever he himself exists.
Further, if, granted a cause, its effect does not immediately
exist as well, this can only be because something complementary
to that cause is lacking: the complete cause and the thing caused
are simultaneous. God, however, never lacks any kind of complementary
cause in order to produce an effect. Therefore, at any instant
at which God exists, so too can his effects, and thus God need
not precede his effects in time.
Further, the will of the voluntary agent in no way diminishes
his power, and this is especially true with God. But all those
who try to answer the arguments of Aristotle (who held that something
caused by God had always existed, since like always makes like) [] say that the conclusion
would follow if God were not a voluntary agent. Therefore, allowing
that God is a voluntary agent, it still follows that he can make
something that he has made never fail to exist. Thus, although
God cannot make contradictories true, we have shown that there
is no contradiction in saying that an agent cause does not precede
its effect in time.
It remains to be seen, then, whether there is a contradiction
in saying that something made has always existed, on the grounds
that it may be necessary that its non-being precede it in time,
for we say that it is made out of nothing. But that there is no
contradiction here is shown by Anselm in his explanation of what
it means to say that a creature is made out of nothing. He says
(Monologion cap. 8), "The third sense in which we
can say that something is made out of nothing is this: we understand
that something is made, but that there is not something from which
it is made. In a similar way, we say that someone who is sad without
reason is sad about nothing. We can thus say that all things,
except the Supreme Being, are made by him out of nothing in the
sense that they are not made out of anything, and no absurdity
results." On this understanding of the phrase "out of
nothing," therefore, no temporal priority of non-being to
being is posited, as there would be if there were first nothing
and then later something.
Further, let us even suppose that the preposition "out of"
imports some affirmative order of non-being to being, as if the
proposition that the creature is made out of nothing meant that
the creature is made after nothing. Then this expression "after"
certainly implies order, but order is of two kinds: order of time
and order of nature. If, therefore, the proper and the particular
does not follow from the common and the universal, it will not
necessarily follow that, because the creature is made after nothing,
non-being is temporally prior to the being of the creature. Rather,
it suffices that non-being be prior to being by nature. Now, whatever
naturally pertains to something in itself is prior to what that
thing only receives from another. A creature does not have being,
however, except from another, for, considered in itself, every
creature is nothing, and thus, with respect to the creature, non-being
is prior to being by nature. Nor does it follow from the creature's
always having existed that its being and non-being are ever simultaneous,
as if the creature always existed but at some time nothing existed,
for the priority is not one of time. Rather, the argument merely
requires that the nature of the creature is such that, if the
creature were left to itself, it would be nothing. For example,
if we should say that the air has always been illuminated by the
sun, it would be right to say that the air has always been made
lucid by the sun. Thus, since anything that comes to be such-and-such
comes to be such-and-such from being not such-and-such, we say
that the air is made lucid from being non-lucid, or opaque, not
because the air was once non-lucid or opaque, but because the
air would be opaque if the sun did not illuminate it. This is
clearly the case with the stars and those celestial bodies that
are always illuminated by the sun.
Thus it is clear that there is no contradiction in saying that
something made by God has always existed. Indeed, if there were
some contradiction, it would be amazing that Augustine failed
to see it, for exposing such a contradiction would be a most effective
way of proving that the world is not eternal, and although Augustine
offers many arguments against the eternity of the world in XI
and XII De Civitate Dei, he never argues that his opponents'
view is contradictory. On the contrary, Augustine seems to hint
that there is no contradiction involved. Thus, speaking of the
Platonists, he says (X De Civitate Dei cap. 31), "They
somehow contemplate a beginning in causation rather than a beginning
in time. Imagine, they say, a foot that has been in dust since
eternity: a footprint has always been beneath it, and nobody would
doubt that the footprint was made by the pressure of the foot.
Though neither is prior in time to the other, yet one is made
by the other. Likewise, they say, the world and the gods in it
have always existed, just as he who made them always existed;
yet nevertheless, they were made." [PL 41, 311] Nor does
Augustine ever say that this cannot be understood; rather, he
proceeds against the Platonists in a totally different way. He
says (XI De Civitate Dei cap. 4), "Those, however,
who admit that the world was made by God but nevertheless want
to hold that the world has a beginning in creation but not in
time, so that, in some scarcely intelligible way, it has always
been made by God, think that they are defending God against a
charge of casual rashness." [PL 41, 319][] Their position is difficult to understand, however, only for the
reason given above in the first argument.
How remarkable it would be that even the most noble of philosophers
failed to see a contradiction in the idea that something made
by God has always existed. Speaking against the Platonists, Augustine
says (XI De Civitate Dei cap. 5), "Here we are contending
with those who agree with us that God is the Creator of all bodies
and all natures except himself," [PL 41, 320] and then, again
about the Platonists, he adds (XI De Civitate Dei cap.
5), "These philosophers surpassed the rest in nobility and
authority." [PL 41, 321] Augustine said this even after diligently
considering their position that the world has always existed,
for they nevertheless thought that it was made by God, and they
saw no contradiction between these two ideas. Therefore, those
who so subtly perceive the contradiction are solitary men, and
with these does wisdom arise. []
Still, since certain authorities seem to argue on the side of
such men, we ought to show that they base themselves on a weak
foundation. Damascene says (I De Fide Orthodoxa cap. 8),
"What is made out of nothing is by nature not such that it
is coeternal to what has no causal principle and always exists."
[PG 94, 814B] Likewise, Hugh of St. Victor says (De Sacramentis I-1 cap. 1), "The ineffable omnipotent power could not have
anything coeternal beyond itself that would help it in making."
[PL 176, 187B]
But the position of these and similar authorities is made clear
by Boethius, who says (V De Consolatione prosa 6), "When
some people hear that Plato thought this world neither had a beginning
in time nor will ever have an end, they mistakenly conclude that
the created world is coeternal with the Creator. However, to be
led through the endless life Plato attributes to the world is
one thing; to embrace simultaneously the whole presence of endless
life is quite another, and it is this latter that is proper to
the divine mind." [PL 63, 859B] Thus it does not follow,
as some people object, that a creature, even if it had always
existed, would be equal to God in duration. For, if "eternal"
be understood in this sense, nothing can in any way be coeternal
with God, for nothing but God is immutable. As Augustine says
(XII De Civitate Dei cap. 15), [] "Time, since it passes away by its mutability, cannot be
coeternal with immutable eternity. Thus, even if the immortality
of the angels does not pass away in time (it is neither past,
as if it did not exist now; nor is it future, as if it did not
yet exist), nevertheless, the angels' motions, by which moments
of time are carried along from the future into the past, pass
away. Therefore, angels cannot be coeternal with the Creator,
in whose motion there is nothing which has been that is not now,
nor anything which will later be that is not already." [PL
41, 364-365] Likewise, Augustine says (VIII Super Genesis ad
Litteram cap. 23), "Since the nature of the Trinity is
wholly unchangeable, it is eternal in such a way that nothing
can be coeternal with it," [PL 34, 389] and he uses words
to the same effect in XI Confessionum as well. []
Those who try to prove that the world could not have always existed
even adduce arguments that the philosophers have considered and
solved. Chief among these is the argument from the infinity of
souls: if the world had always existed, these people argue, there
would necessarily be an infinite number of souls. But this argument
is not to the point, for God could have made the world without
making men or creatures with souls, or he could have made men
when in fact he did make them, even if he had made the rest of
the world from eternity. In either case, an infinite number of
souls would not remain after the bodies had passed away. Furthermore,
it has not yet been demonstrated that God cannot cause an infinite
number of things to exist simultaneously.
There are other arguments adduced as well, but I refrain from
answering them at present, either because they have been suitably
answered elsewhere, or because they are so weak that their very
weakness lends probability to the opposing view.
 This translation
follows the Leonine Edition of Aquinas's works, vol. 43 Sancti
Thomae De Aquino Opera Omnia 85-89 (Rome 1976).
 All persons
are licensed to reproduce this translation and the footnotes hereto
for personal or educational purposes, provided that the notice
of copyright above and this notice are included in their respective
entireties in all copies. This license includes reproduction by
a commercial entity engaged in the business of providing copying
services if such reproduction is made at the behest of a person
who would otherwise be licensed under the preceding sentence to
reproduce this translation for personal or educational purposes.
 Aquinas means
that the impossibility may be thought to arise either on the part
of God, as if he were unable to make such a thing for lack of
power, or on the part of the thing, as if such a thing could not
be made because it lacks a pre-existing passive potentiality or
because it is self-contradictory.
 That is, on
the condition that such a thing can be made. In other words, all
sides agree that the impossibility of something having always
existed, if such there be, does not arise from some lack of power
 That is, between
"always having existed" and "having been made."
 In the sense
that there was nothing existing before the angel that would become
the angel, as the brass to be made into a statue exists before
the statue and becomes the statue.
 See II De
Generatione et Corruptione cap. 10, 336a 27-28.
 PL 41, 319.
In the Leonine Edition, Aquinas does not quote the predicate of
the independent clause; it does appear in the Parma Edition, and
I have chosen to supply it.
 Said ironically,
the sentence is quite out of character for Aquinas, who courteously
conducted the bitterest disputations. Here he is probably alluding
to the Vulgate text of Job 12:2, in which Job says, "You
are solitary men, and with you wisdom shall die." The difference
between "arises" (oritur) and "shall die"
(morietur) is small.
 So in Aquinas.
The chapter divisions in De Civitate Dei are, at this point,
somewhat unclear, and, as the editors of the Leonine Edition suggest,
the quoted text is probably from cap. 16. In any event, the quoted
material appears at PL 41, 364-365.
 See XI Confessionum cap. 30. PL 32, 826.
This text is part of the Internet Medieval Source Book.
The Sourcebook is a collection of public domain and copy-permitted
texts related to medieval and Byzantine history.
Unless otherwise indicated the specific electronic form of the
document is copyright. Permission is granted for electronic copying,
distribution in print form for educational purposes and personal
use. If you do reduplicate the document, indicate the source.
No permission is granted for commercial use.
Paul Halsall May 1997