Entry 0222: Origin of the Five Ways
It is generally accepted that Aquinas's Five Ways of proving the existence of God have their ultimate source in Aristotle. Aquinas is not the originator of the arguments.
See for example Leo J. Elders's The Philosophical Theology of St. Thomas Aquinas, (Leiden, The Netherlands: E. J. Brill, 1990), 83-126.
Fergus Kerr offers the following remarks:
“One thing is not always made
clear: Aquinas does not regard the Five
Ways as his own arguments, nor does he regard them
as arguments which might or might not work. Rather, he regards them as
arguments that already have worked.
In the parallel discussion in the Summa
contra gentiles he takes much more time and trouble but even there it is
surely plain that he is only rehearsing what he regards as ancient and familiar
arguments.
“Admittedly, when Aquinas spells
out the First Way, based on the obviousness of change in the world, he does not
explicitly refer to Aristotle; but the parallel passage in Summa contra gentiles (I, 13) shows clearly enough that he knows
that Aristotle is the source of the argument. The Second and Third Ways, based on efficient
causality and the fact that some things have the possibility of being or not
being, respectively, have equally clear roots in Aristotle.
“The Fourth Way, invoking degrees
of being, goodness, truth, and so forth, the only one in which Aquinas cites
Aristotle explicitly, is, paradoxically, as it might seem to us, distinctly
Platonist in origin and inspiration. In fact, for all his involvement in the
retrieval of Aristotelianism, it has been shown in the last fifty years or so
that Aquinas remains profoundly indebted to Platonism.
“No authority is cited for the Fifth Way, from
design or teleology, but the brief exposition recalls the most ancient and
persistently popular argument of all, dating back to Plato and the Stoics as
well as to Aristotle. While of course most of Plato’s texts were unavailable,
and there is little sign that Aquinas knew much of the Stoic literature at
first hand, it is surely clear that he takes it for granted that he is
expounding a very familiar argument.” (1)
(1) Fergus Kerr, “Theology in Philosophy: Revisiting the Five Ways,” International
Journal for Philosophy of Religion 50
(2001): 115–130.
Origin of the Five Ways (I)
Concerning the sources of Aquinas’ Five Ways, Leo J. Elders comments that
“The Five Ways
of St. Thomas
are a summary and transposition into a unified structure and stringent form of
more than sixteen hundred years of philosophical efforts to prove God's
existence. St. Thomas
himself was very much aware of the fact that he was using materials from
philosophical tradition.”
More specifically, concerning the First Way, Elders remarks that
“In the First Way Aristotle’s analysis of motion which St. Thomas himself fully endorses is used … St. Thomas’ argument is
directly dependent on Aristotle's demonstration of the existence of the First Unmoved
Mover.”
Then, considering the First Unmoved Mover, Elders continues,
“It is surprising to see that after Aristotle the argument
is seldom used. The idea of a First Mover at the outside of the universe may
have held little attraction. The argument was perhaps disregarded by Christians
because it was thought to be connected with the theory of an eternal world.
However, it made its influence felt inasmuch as it contributed to the general
admission of God's total immutability …”
Elder finally concludes his commentary on the sources of the
First Way
by saying that
“Thomas main sources were the texts in
Aristotle’s Physics and Metaphysics.” (1)
Note
(1) Leo J. Elders, The
Philosophical Theology of St. Thomas Aquinas, (Leiden, The Netherlands: E.
J. Brill, 1990), 90-91 and 95-96.
Origin of the Five Ways (II)
On the sources of Aquinas’ Second Way of
demonstrating the existence of God, Leo J. Elders remarks that
“In Summa contra gentiles I, 13 Aquinas seems to ascribe the argument
to Aristotle. However, upon closer inspection the text does not say more than
that Aristotle shows that in a series of efficient causes infinite regress is
not possible and that, therefore, there must be a first.”
Elders then explains that “Aristotle's
text is found in Metaph. II (a) 2,
994 a 1ff., where he [Aristotle] sets forth the principle that in a series of
causes, whether material, formal, efficient, or final, there must be a first, but
it is not used as a demonstration of God's existence. Aristotle could hardly
have done so because God is neither a first material nor a first formal cause.
In his commentary on the text Aquinas refrains from reading a demonstration of
God's existence into these lines.”
Finally, Elders concludes by saying that “Van
Steenberghen's statement [in Le probleme
de l'existence de Dieu dans les écrits de S. Thomas d'Aquin, Louvain-la-Neuve,
1980, p. 187] that the Second Way
is entirely taken from Aristotle must be qualified.” (1)
Note
(1) Leo J. Elders, The
Philosophical Theology of St. Thomas Aquinas, (Leiden, The Netherlands: E.
J. Brill, 1990), 100.
Origin of the Five Ways (III)
Regarding the Third Way, Leo Elders affirms that for
Aquinas the possibility of being and of not being belongs to things on account
of their matter. And more specifically regarding the influence of Aristotle,
Elders affirms that “The ‘it is impossible that these things always exist’ is a
principle given by Aristotle in the De
caelo 1 cc. 10-12 and accepted by St. Thomas who even explains it in a
subsequent line: ‘for that which can not-be, at some point is not.’ This
statement is the central point of the argument: a corruptible thing which would
never cease to exist, would have the possibility of not being corrupted, while
at the same time it is corruptible. But this is impossible. (See In I De caelo, 1.29, n.283 and 1.26,
n.257.)” (1)
Later Elders explains that
regarding the influence of Aristotle on the Third Way, “some have pointed out
to Metaph. XII 6, 1071 b 22-27 as the
source of the argument: What is possible, does not have existence of itself but
depends on something in act; of itself a possible being remains in potency;
from the point of view of possibility alone at some time nothing is.” And then Elders adds that “More
recently scholars have drawn attention to the De caelo I 12, where the statement is found: ‘What can not be, at a
certain time is not.’ With this insight Aristotle provided an essential element
for the argument as we find it in the Summa
theologiae.” (2)
(1) Leo
J. Elders, The Philosophical Theology of St. Thomas Aquinas,
(Leiden, The Netherlands: E. J. Brill, 1990), 102-103.
Origin of the Five Ways (IV)
Regarding the sources of the Fourth Way, Leo
Elders pointed out that “it is remarkable that both in the Summa contra gentiles, I, 13 and in the Summa theologiae, I, 2, 3 as well as in the Quaestio disputata de potentia, 3, 5, Aquinas refers to Aristotle.
The texts of the Corpus quoted are Metaph. II 993 b 24 f. and IV 1004 b 2
ff (there are degrees in falsehood, therefore also in truth). The principle
formulated by Aristotle has already been discussed in our analysis.”
In the analysis, Elders asks “How can we proceed from the existence of limited perfections to
that of an unlimited being?”
And he answers that “St. Thomas has taken over
from Aristotle or rather from the Corpus
Aristotelicum the principle: ‘That which gives other things a certain form
or perfection has itself this perfection to the highest degree.’ However, Aquinas uses the maxim in a different way and
states that where a perfection is found according to more or less there must be
something which has it most.”
“Although the doctrine of
participation is hardly Aristotelian,” Elders continues, “Aristotle
nevertheless admits that at the level of efficient causality there is a first
and a maximum with regard to qualities. He uses the example of fire as an
illustration.”
The footnote attached to this
affirmation reads as follows: “Metaph.
II (a) 1, 993 b 25: fire is hottest and so it is to other things the cause of
their heat. Aristotle presents an argument from the degrees of being in the De philosophia, fr. 16. See De ideis, fr. 3. One may also compare Met. 1055a 3 ff.”
Elders then adds, “Above all
Aristotle teaches the unity of being, which to St. Thomas is of paramount importance: the
transcendentals coalesce in the unity of the concrete thing and do not
constitute juxtaposed distinct formal realities.”
Elders further explains
that “The transcendentals are modes of being rendering explicit what is already
contained in things. Being shows itself in the perfections it exhibits. For
this reason St. Thomas
can pass from the transcendental concepts to a conclusion about being. He does
so with the help of an argument borrowed from Metaphysics II 1: ‘Things which are truest, are also most being.’ In
this chapter Aristotle shows that the highest things, viz. principles and
causes, are truest because they are the ground of our knowledge and certitude. St. Thomas changes the
order somewhat and argues from truth to being. The argument is valid, for
‘truest’ is that being which also communicates its truth to others. This is
what causes do.”
Finally, Elders points out
that “In De substantiis separatis
(chapter 3) St. Thomas
describes Plato’s doctrine of participation and explains to what extent it
agrees with Aristotle views.” (1)
(1) Leo
J. Elders, The Philosophical Theology of St. Thomas Aquinas,
(Leiden, The Netherlands: E. J. Brill, 1990), 113-119.
Origin of the Five Ways (V)
Concerning Aristotle’s influence
on the formulation of the Fifth
Way, in his The Philosophical Theology of St. Thomas Aquinas,
([Leiden, The Netherlands: E. J. Brill, 1990], 121-125) Leo Elders writes:
“The teleological argument is
that proof of God’s existence which is most widely found in religious and
philosophical tradition. The reason is that it is obvious to man that order
does not come from nothing but requires someone who arranges things.
“In the prologue to the Lectura super Evang.
Ioannis St. Thomas calls this the most efficacious way.
“Aristotle gives a version of
this proof of God in De philosophia
(Fr. 10 R). And in Metaph. XII 10,
1076 a 3 Aristotle attributes to Homer the thesis that there must be one principle
which governs the cosmos.
“St. Thomas agrees with Aristotle that this
teleological organization shows most in animal life (In II Phys., I.13, n.259).
“Against the objection that it is
impossible to speak of finality in inanimate bodies, St. Thomas maintains that natural things
without knowledge act for an end, because they always act in the same way so as
to obtain the best result (‘id quod est optimum’).
“What does Aquinas mean by his
statement that these natural things are always or almost always acting in the
same way and reach what is best? When we read this text against the background
of the commentary on Aristotle’s Physics
II, lesson 13 which explicitly studies this question, we notice that to act for
an end is distinguished from chance events. What happens by chance is not directed
towards a certain purpose. The classic example is that of a tile falling from a
roof which hits a pedestrian who happens to be passing.
“It is impossible that things
which happen always or in most cases in the same way, come about by chance. (The
wording of the first lines of the Fifth
Way is very close to Aristotle’s text [Phys. II, c.8] and that of St. Thomas commentary [ibid.,
n.256]). The reason is that in chance events there is no intended connection
between an action and the result obtained. Therefore this result comes about in
a capricious manner.
“In the activity of natural
things where there is a final term, there is an intended connection between the
action itself and its result.
“St. Thomas explains this in his already
quoted commentary: when something is done naturally in a certain way, it has a
natural disposition and aptitude (‘aptum natum est’) to be done in this way (In II Phys., n.257). This is precisely
what Aristotle writes himself: ‘and as they are by nature such as to be, so
they are done, if there is no impediment’ (Phys.,
199 a 10 transl. by W. Charlton).
“What Aristotle writes is
obvious: every year in spring the sun climbs higher in the ecliptic, it warms
the atmosphere and the higher temperature melts the snow; the chemical elements
react with one another according to a set affinity; in the course of the
seasons of the year plants act always or almost always in a regular pattern to
reach certain ends. They do so according to their natural aptitude. Nature has
fitted them out in such a way that these activities follow conveniently and
easily. (See In II Phys., I,12,
n.252.)”
God's Existence versus God's Actus Essendi
It
is well known that the question “Does God exist?” had an affirmative answer before
the time of Saint Thomas Aquinas. The discovery of the notion of actus essendi was not needed to put to
rest the issue of God’s existence. The historical path of the philosophical
demonstration of the existence of God is the historical path of a judgment of
existence applied to God.
The
issue of the definition of the essence of God in terms of the metaphysical
principle of actus essendi, on the
other hand, is not only an issue different from the issue of God’s existence,
it is also an issue that took a different historical path in its development.
Aquinas was indeed able to express the human intellect’s awareness of the real
in the technical terminology of the actus
essendi, but there is no question that before the discovery of the notion
of actus essendi, answers to the question “Does
God exist?” had been given in terms of a judgment of existence.
In his understanding
of esse, Aquinas distinguished
clearly between the esse that answers
the question of existence (the question an sit) and the esse
that connotes the metaphysical principle of actus
essendi. And here something that may seem obvious needs to be emphasized.
After the discovery of the notion of actus
essendi, the issue of how to reason and conclude correctly about God’s actus essendi is not to be confused with
the issue of how to reason and conclude correctly about God’s existence.
John Haldane on the First and Fifth Ways
In a recent interview, Professor John Haldane was
asked: “Aquinas’ famous cosmological argument is partly famous because it has
been subjected to huge critical study and would seem to have been rendered
obsolete. Haven’t developments in modern logic after Frege left much of Aquinas
generally in a mess? Doesn’t too much of the original system – brilliant though
it was in the time he was writing – depend on errors that subsequent
generations have discovered?”
Professor Haldane answered: “There are several
places in Aquinas’ writings where he refers to natural philosophy, i.e. to what
we would consider empirical science, and makes statements that we now know to
be false. Examples concern human physiology, conception and embryological
development, and aspects of physics, chemistry and astronomy. Where these are
invoked in arguments, e.g. about sensation, the beginnings of life, or the
nature of the heavenly bodies the result may be to render arguments unsound,
but the deeper issues are generally metaphysical and the interesting question
is whether the arguments can be reformulated in terms of corrected empirical
facts, and how far such reformulation takes one away from Aquinas’ central
purpose.
“So far as arguing to the existence of God is
concerned, Aquinas’ main lines of argument do not depend essentially on
particular empirical theories. These are set out in the ‘Five Ways’ presented in
the second question of his major work the Summa
Theologiae, but there are other arguments elsewhere.
“Let me mention two lines of reasoning one
teleological, the other cosmological.
“Aquinas claims that the action of some natural
organisms is explicable in terms of the ends towards which they move, even
though they lack intelligence. These ends generally confer benefits relevant to
the natures of the organisms and hence conduce to their good. If we thought of
these agents as choosing the ends then we might think that no further
explanation was called for, but if they are incapable of choice then there must
be some other explanation of their tendencies towards beneficial states,
something external and directional, and from this Aquinas reasons to the idea of
a benign designer, saying that this is what we call God (‘et hoc dicimus Deum’).
“There is much that has been said about this kind
of argument and it is commonly supposed to have been defeated by the theory of
evolution through mutation and natural selection. But evolutionary speciation
itself rests on teleologically-structured processes which it does not and
cannot explain. There is much more to be said and if readers want to see how
this debate might develop they could look at my debate with the late Jack Smart
in Atheism and Theism. Here all I
want to point out is that the argument neither excludes nor is rendered unsound
by evolutionary processes.
“The second argument is that involving essence and
existence – and by existence I mean actuality or ‘be-ing’, i.e. existing. In
this sense existence is a metaphysical aspect of any existing thing and it is
not captured by the existential quantifier.
“Aquinas points out that if we were to inquire into
some kind of entity we might ask what is it? i.e. ask about its nature or
essence, but also ask is it? does it actually exist? The fact that the second
question remains open even when the first has been answered shows that the
existence of the thing does not follow from its essence. So if it exists its
existence must derive from something else.
“Of that prior source one can again ask whether its
existence is implied by its nature and if not then we have to look for a
further source, and so it continues. If a vicious regress is to be avoided we
must suppose that there is something in which existence is implied by essence
and which has the power to confer existence on other things. So again Aquinas
is led to the idea of God as the creator, and indeed sustainer of the being as
well as of the natures of beings. While this argument may be contested it is a
purely metaphysical one and does not rest on particular empirical claims and
hence is not refutable by appeal to scientific discoveries.”
The interview was first published by “3:AM Magazine”
on Tuesday, 4 December 2012 under the title “Aquinas amongst the Analytics.”
Link to
the full interview:
http://www.3ammagazine.com/3am/aquinas-amongst-the-analytics/