The book is Proclus' Elements of Theology
. By 1017 this fifth-century text had likely
made its way to Dar al-Hikma. It would have been slotted in the cabinet
beside its more popular (and pseudonymous) abridgment, (Aristotle's) Discourse on the Pure Good
, later known as the Book of Causes
The Elements of Theology is Proclus' systematic exposition
of Neoplatonism. Its primary deduction — the immortality of the soul.
The Elements may be the most orderly proof of
immortality ever composed by a Hellenic philosopher. In this essay I will present a few
Elements which abstract Proclus' argument. This presentation will pass quickly to a critique.
The critique brings Proclus' image of the soul into focus, as it disentangles
the knot of his immortality argument.
This exercise in criticism is preparation for the modern metaphysical thesis which is to come — and it's an exercise which this author dislikes.
I must raise critical remarks across three ascending chapters before I can pause to bolt the remarks together, as a single thought, in the preparatory conclusion of Chapter 7.
Many readers may imagine the critical material to be unnecessary, or even pointless. It is neither — but here I think a
proper explanation would run too far ahead, so I'll refrain. Chapter 7 will come soon enough. Only, here especially I must beg for the reader's
patience and trust.
We take up the seamed volume. Leather opens to paper, paper opens to words.
The text of Proclus' Elements
consists of two hundred and eleven Neoplatonic propositions,
organized by a method similar to that which mathematicians use in the
construction of mathematical proofs.
When a mathematician wants to prove a novel theorem, he uses
in his proof theorems which have been proved before. Those axioms are
foundational, in the sense that they are uncontroversial and accepted as
authoritative by the mathematical community.
In the same
spirit Proclus starts at first principles, intuitively. He builds on this foundation, citing his
foundational propositions as the authorities for subsequent arguments.
Proclus may have chosen his method with a mathematical structure in mind.
Be that as it may, the work is ordered logically.
He composes each proposition of two parts: an argument and a conclusion. (In
mathematical terms, the argument is analogous to a proof, and the
conclusion to a theorem proved axiomatically.)
comes first. Proclus states it in a single sentence.
conclusion comes the argument, in which Proclus deduces the conclusion he has
just stated. Each argument is one paragraph in length.
few choice propositions will make clear Proclus' method. Ten of
the 211 propositions are reprinted below.
propositions constitute a significant portion of Proclus' argument for the
soul's indestructible and imperishable nature. The propositions are
cogent, although numbered in a way which puts the selected ten slightly out of
order when read in isolation. For this reason I have moved two
propositions forward. So ordered the selected ten state much of
Here are the ten
propositions, reprinted in full, with notes. Afterwards,
a twenty-first-century critique
of Proclus' noble fifth-century thoughts.
Ten propositions from Proclus' Elements of Theology
Prop. 33. All that
proceeds from any principle and reverts upon it has a cyclic
For if it reverts upon that principle whence it
proceeds (Prop. 31), it
links its end to its beginning, and the movement is one and continuous,
originating from the unmoved and to the unmoved again returning. Thus
all things proceed in a circuit, from their causes to their causes
again. There are greater circuits and lesser, in that some revert upon
their immediate priors, others upon the superior causes, even to the
beginning of all things. For out of the beginning all things are, and
towards it all revert.
Proposition 33 introduces "cyclic
activity," conceived as the necessary return of any created thing to the
source of its creation. The water cycle may serve as an illustration of
The sun frees water from the ocean as vapor. That vapor
"proceeds" away from the ocean; forming clouds, raining upon the land,
and trickling into rivers. The rivers "revert" the water to its
origin, the ocean. Proclus envisions all existence as running through
such reversive cycles.
Prop. 17. Everything originally self-moving is capable of reversion upon
For if it moves itself, its motive
activity is directed upon itself, and mover and moved exist simultaneously
as one thing. For either it moves with one part of itself and is moved
in another; or the whole moves and is moved; or the whole originates motion
which occurs in a part, or vice versa
if the mover be one part and the moved another, in itself the whole will not
be self-moved, since it will be composed of parts which are not self-moved:
it will have the appearance of a self-mover, but will not be such in
essence. And if the whole originates a motion which occurs in a part,
or vice versa
, there will be a part common to
both which is simultaneously and in the same respect mover and moved, and it
is this part which is originally self-moved. And if one and the same
thing moves and is moved, it will (as a self-mover) have its activity of
motion directed upon itself. But to direct activity upon anything is
to turn towards that thing. Everything, therefore, which is originally
self-moving is capable of reversion upon itself.
Proposition 17 examines cyclic activity in
a self-motive body. Such a body is both its originating cause and also its
effect; both a beginning and an end. By Proposition 33 the cause to which
it reverts must therefore be itself.
Prop. 15. All
that is capable of reverting upon itself is incorporeal.
For it is not in the nature of any body
to revert upon itself. That which reverts upon anything is conjoined
with that upon which it reverts: hence it is evident that every part of a
body reverted upon itself must be conjoined with every other part —
since self-reversion is precisely the case in which the reverted subject and
that upon which it has reverted become identical. But this is
impossible for a body, and universally for any divisible substance: for the
whole of a divisible substance cannot be conjoined with the whole of itself,
because of the separation of its parts, which occupy different positions in
space. It is not in the nature, then, of any body to revert upon
itself so that the whole is reverted upon the whole. Thus if there is
anything which is capable of reverting upon itself, it is incorporeal and
Proposition 15 explores the meaning of
"conjunction": the joining of parts adjacent to one
another. Conjunction is only possible where parts are immediately
adjacent. Parts more distant are not conjoined. As corporeal bodies
are composed of parts located at various distances from one another, those parts cannot wholly
conjoin. Unfortunately, self-reversion requires just such a conjunction. It follows that self-reverting entities must
be without parts; hence, incorporeal.
Prop. 16. All
that is capable of reverting upon itself has an existence separable from all
For if there were any body whatsoever
from which it was inseparable, it could have no activity separable from the
body, since it is impossible that if the existence be inseparable from
bodies the activity, which proceeds from the existence, should be
separable: if so, the activity would be superior to the existence, in
that the latter needed a body while the former was self-sufficient, being
dependent not on bodies but on itself. Anything, therefore, which is
inseparable in its existence is to the same or an ever greater degree
inseparable in its activity. But if so, it cannot revert upon itself:
for that which reverts upon itself, being other than body (Prop. 15), has an
activity independent of the body and not conducted through it or with its
co-operation, since neither the activity itself nor the end to which it is
directed requires the body. Accordingly, that which reverts upon
itself must be entirely separable from bodies.
Proposition 16 strengthens Proposition
15. It argues that any taint of corporeality on a
self-reversive entity would render self-reversion impossible. For this
reason self-reversion must be not only incorporeal, but also cleanly separable
from all corporeal bodies.
Prop. 43. All
that is capable of reversion upon itself is self-constituted.
For if it is by nature reverted upon
itself, and is made complete by such reversion, it must derive its existence
from itself, since the goal of natural reversion for any term is the source
from which its existence proceeds (Prop. 34).
If, then, it is the source of its own
well-being, it will certainly be also the source of its own being and
responsible for its own existence as a substance. Thus what is able to
revert upon itself is self-constituted.
Proposition 43 equates
"well-being" with completion of the reversive cycle. If an
incorporeal body can act as the source of its own well-being by reverting upon
itself, it is considered to be self-constituted.
Prop. 46. All
that is self-constituted is imperishable.
For if it be destined to perish, it
will then desert itself and be severed from itself. But this is
impossible. For being one, it is at once cause and effect. Now
whatever perishes is in perishing severed from its cause: for each thing is
held together and conserved so long as it is linked with a principle which
contains and conserves it. But the self-constituted, being its own
cause, never deserts its cause since it never deserts itself.
Therefore all that is self-constituted is imperishable.
Proposition 46 draws upon Proposition 43 in
arguing for the imperishable nature of the self-constituted. The self-constituted
is imperishable because it is never severed from its principle cause (which is itself).
Prop. 49. All
that is self-constituted is perpetual.
For anything which is not perpetual
must be so in one of two ways, either as being composite or as existing in
But the self-constituted is simple, not composite
exists in itself, not in another (Prop.41).
It is therefore perpetual.
Proposition 49 argues that the
self-constituted exists perpetually because it has no composite parts susceptible to
decomposition; and also because it exists without external aid.
Prop. 83. All
that is capable of self-knowledge is capable of every form of
For that it is self-reversive in its
activity is evident, since it knows itself: knower and known are here one,
and its cognition has itself as object; as the act of a knower this
cognition is an activity, and it is self-reversive since in it the subject
knows itself. But if in activity, then also in existence, as has been
shown: for everything whose activity reverts upon itself has also an
existence which is self-concentrated and self-contained (Prop. 44).
Proposition 83 addresses cognition for the
first time. Cognition is shown to be a kind of self-reversive activity, as
demonstrated in the act of self-knowledge. Hence self-knowledge must share
in those traits common to any self-reversive activity. For example, it
must have an existence which is self-contained. (By inference, its existence must
also be self-constituted, per Prop. 43.)
Prop. 186. Every soul is an incorporeal substance and separable from body.
For if it know itself, and if whatever
knows itself reverts upon itself (Prop.83), and what reverts upon itself is
neither body (since no body is capable of this activity [Prop.15]) nor
inseparable from body (since, again, what is inseparable from body is
incapable of reversion upon itself, which would involve separation
[Prop.16]), it will follow that soul is neither a corporeal substance nor
inseparable from body. But that it knows itself is apparent: for if it
has knowledge of principles superior to itself, it is capable a fortiori
itself, deriving self-knowledge from its knowledge of the causes prior to
Proposition 186, like Proposition 83,
applies previous results to the special activity of cognition. The results
apply equally to cognition's home, the soul. The soul, being self-knowing,
must also be incorporeal and separable from the body.
Prop. 187. Every soul is indestructible and imperishable.
For all that is capable of being in any
way dissolved or destroyed either is corporeal and composite or has its
being in a substrate: the former kind, being made up of a plurality of
elements, perishes by dissolution, while the latter, being capable of
existence only in something other than itself, vanishes into non-existence
when severed from its substrate (Prop. 48).
But the soul is both incorporeal and
independent of any substrate, existing in itself and reverting upon itself
(Prop. 186). It is therefore indestructible and imperishable.
Proposition 187 culminates Proclus' case
for the soul's indestructible and imperishable nature. Proclus will
proceed to interpret this result as support for a theory in which the soul
undergoes an unceasing cycle of reincarnations.
Ten propositions from
have now been arranged for display, propped on velvet steps as it were. It's time to subject these propositions to a test of truth — an unfettered critique of Proclus'
next Chapter 4: Reversion in the Corporeal
Chapter 3 Endnotes
The Iraqi encyclopedist al-Nadim listed Proclus' Elements of Theology
in his bibliographical dictionary
, A.D. 987. See Majid
A History of Islamic Philosophy
Columbia University Press, 1970) 40. Apparently Proclus' original text had
been translated and was in circulation among Arab scholars by that time. (This inference
is not certain: no complete Arabic translation from that era has yet been found.) See also: Encyclopaedia Britannica articles on
and Arab thought
Proclus was himself a capable mathematician. See, for
example, his commentary on Euclid's
, as in:
Proclus, Proclus: A Commentary on the First Book of
, trans. Glenn R. Morrow (Princeton: Princeton University
Proclus may have written the Elements of
as a continuation of his Elements of
. See E. R. Dodds, trans., intro., and commentary, The Elements of Theology
, by Proclus, 2nd
ed. (Oxford: Clarendon Press, 1963) xvii-xviii. Proclus' style follows that of mathematical synthesis (deduction),
and also Platonic hypothesis. See Dodds 1963, xi, note 4.
For examples of logical weaknesses, see Dodds 1963, xi-xiii.
All quotations from Dodds 1963.
Dodds 35, Prop. 31. "
proceeds from any principle reverts in respect of its being upon that from which
This implies another syllogism, whose conclusion Proclus does not
draw. Premising Props. 17 and 15, Proclus could conclude that self-moving bodies are also incorporeal. Proclus does not, however, compose the
Dodds 37, Prop. 34. "
Everything whose nature it is to revert reverts upon that from which it derived
the procession of its own substance."
Dodds 49, Prop. 48. " All that
is not perpetual either is composite or has its subsistence in
Dodds 47, Prop. 47. " All that
is self-constituted is without parts and simple."
Dodds 43, Prop. 41. " All that
has its existence in another is produced entirely from another; but all that
exists in itself is self-constituted."
Dodds 77-79, Prop. 44 . "All
that is capable in its activity of reversion upon itself is also reverted upon
itself in respect of its existence."
Dodds 49, Prop. 48. " All that
is not perpetual either is composite or has its subsistence in
Dodds 181, Prop. 206.
particular soul can descend into temporal process and ascend from process to
Being an infinite number of times."