Aristotle's Definitions of the Soul: "De Anima" ii, 1-3

Aristotle's Definitions of the Soul: "De Anima" ii, 1-3
Author(s): Robert Bolton
Reviewed work(s):
Source: Phronesis, Vol. 23, No. 3 (1978), pp. 258-278
Published by: BRILL
Stable URL: http://www.jstor.org/stable/4182048 .
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Aristotle's definitions of the soul: De A nima
II, 1-3
ROBERT BOLTON
Just as in public assemblies they are accustomed
to newly introduce a law and if the
law newly introduced is better they abandon
the previous law, so ought one to proceed in
the case of definitions as well and to propose,
oneself, an alternate definition. For if
it is seen to be better and makes the thing
defined clearer it is obvious that the
definition in force will have been abandoned,
since there are not several definitions
of the same thing,
Topics 151 b 12-17
1. It is a philosophical commonplace that Aristotle's definition of the soul
as the form of the body contains an important anti-dualist solution to the
mind-body problem. It is also widely understood that Aristotle was not
entirely unbending in his attachment to an anti-dualist solution of the
problem. He claims in various places that the intellect is not the form of any
type of body and, hence, is capable of existence as a functioning entity
separate from the body. And he is committed to the existence of an
ensouled but immaterial living being, the prime mover, who not only
carries on the psychic activity of thinking but derives the greatest pleasure
from it. Various attempts have been made to either explain away the
doctrines which seem to conflict with the anti-dualist thrust of the
definition or to minimize their importance in Aristotle's most mature
thought. But none of these attempts has yet managed to secure and maintain
significant support.'
I want to offer here a new suggestion for dealing with the problem. My
proposal is that the structure of the familiar definition of the soul as the
form of the body has not been properly understood. When this is correctly
understood, I shall argue, the definition can be seen to be consistent with
the doctrine of the prime mover, with the theory of the separate intellect
and, most interestingly perhaps, with various types of mind-body dualism.
I begin with a consideration of a little noticed matter.
2. The well-known definition of the soul, as the form of a certain kind of
body, in De Anima II, 1, is offered as an account which mentions something
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common to every soul (nrL XOLVOV rri. %&1s 4'Xis, 412 b 4). But at the end of
the chapter Aristotle confesses that this account is merely a "rough general
account sketched in outline" (ri . . . 'ooyEypa&pq&, 413 a 9-10). This
indicates, somewhat surprisingly, that the account is in some way imperfect.
But in what way?
The significance of the language which Aristotle employs to qualify his
definition is revealed most fully in the Topics and in the History ofAnimals.
An account "in outline" ('rmT) is, according to the Topics, a general
(xa06Xov) account which does not give an "accurate definition" (&xpLpls
X6yos) but which does permit us to know (yvwpieLv) the thing described in
some way (101 a 18-24). For Aristotle there are two ways in which some
thing may be made known, either by reference to what is prior and more
intelligible to us or to what is prior and more intelligible absolutely (141
a 28-30, b 3-19; cf. PosteriorAnalytics 71 b 33, ff.). An account "in outline"
belongs clearly to the former type. An account by reference to things that
are more intelligible absolutely conforms to "accurate understanding"
(&XpLS BLavoLCL) and this is the opposite of what is given in an account "in
outline" (141 b 5-14, 101 a 21 33).2 History of Animals 491 a 7-14 (which
closely parallels De A nima 413 a 9-20) further describes an account "in
outline" as one which gives derivative facts ('ar avA1O3x6'ra) about something
in contrast to giving the theoretical principles (alr(aL) by reference to
which such facts are explained.3
The opening lines of De Anima 11, 2 characterize in detail the differences
between that sort of account which is more familiar to us and which merely
states some fact (TOr 6'rL) and its more perfect counterpart. Since, as we have
just seen, the former type of account is the account "in outline", these lines
give us the reasons which must have led Aristotle to think that the account
in outline in II, 1 was imperfect. The reasons are these! (1) The initial
account while more obvious (qvepvrpepos) than others is still obscure
(&aacp's) and so in need of replacement by one which is more intelligible in
the order of explanation (xarar 'rv Xoyov yvpW+u.'repos) (413 a 11-13). (2)
The initial account shares the fault of most definitions which people give of
merely displaying something that is the case ('rO 8rL) without giving the
essence (oUria) of the thing defined (413 a 13-16). (3) The initial definition
is like a conclusion (av1LuipaaVc) about the thing defined rather than a
statement of the reason ('ob a'L'TLov) for such conclusions (413 a 16-20).
Given that Aristotle is contrasting here the type of definition of which the
famous account of the soul in II, 1 is an instance with another superior
type,4 we need to ask what these contrasts imply as to the exact content of
the definition of II, I and as to what precisely the defects of that definition
are.
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3. As commentators have pointed out, the contrasts drawn in brief
between different types of definition at the beginning of DeeAnima 11, 2 are
laid out at more length in the Posterior Analytics, especially in Book II,
chapters 8-10. But the significance of that discussion for our questions
concerning the status of the definition of the soul in De A nima II, I has not
been fully explored.
Before turning to the Analytics, however, it will be useful to describe in
some detail various problems of interpretation in De A nima II, 1-3 which
are connected with our questions about the definition of II, 1. Light can, I
think, be shed on all these problems by attention to the theory of types of
definition in the Posterior Analytics.
The first group of problems worth our attention here has to do with the
content of the definition in II, 1 - or, as we should say, of the definitions in
II, 1, since there is more than one. Are these various definitions equivalent?
Here are the definitions which Aristotle offers us:
(1) Soul is the substance, in the sense of the form, of a natural body which
has life potentially (412 a 19-21).
(2) Soul is the first actuality of a natural body which has life potentially
(412 a 27-28).
(3) Soul is the first actuality of a natural body which has organs (412 b
5-6).
(4) Soul is the essence and defining principle (Xoyos) of that sort of natural
body which has within itself a source (&px~) of its change and stability
(412 b 15-17).5
We may allow that the first two definitions which Aristotle gives us pose no
problem in relation to each other since he gives the second simply to
explain what he means by the first. But the third - the account of soul as
the first actuality of a natural body with organs - raises apparent difficulties.
Aristotle treats soul as the principle of life; things are ensouled if and
only if they have life (413 a 21-2). But must something have organs to be
alive? In fact we know that certain microscopic living creatures are
composed of undifferentiated living tissue. They engage in life functions
such as nutrition and reproduction without employing any organs for those
functions and do not possess any organs at all in the sense of parts which
perform distinctive functions not performed by other parts (cf. De Partibus
Animalium 645 b 3 ff., at 14). We might well suppose that Aristotle didn't
allow for this because of his inadequate understanding of biology. But
Aristotle himself regards certain material objects, namely the stars, as alive
even though he believes that their matter is undifferentiated and cannot be
altered or moved internally in any way and that, hence, they do not have
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organs.6 This apparent inconsistency holds, moreover, not only between
the third definition and things Aristotle says elsewhere. It holds between
the third definition and the second. The second definition requires only
that to be ensouled7 a body must be in a certain state of readiness to engage
in one or another life function, whether it has organs or not. It will be said
that Aristotle wants to argue in the De A nima that only a body with organs
could be in such a state. But he doesn't argue for this. At best he merely
claims it (412 a 28, f.). And even this he does not do unambiguously. For he
allows that if a thing engages regularly by nature in patterned change of
place that is enough to make it alive (413 a 22-25). We know that he
believes that the stars and the spheres in which they move do this and that
he denies that they have organs. So we have good reason to want the second
definition of soul to cover the stars. If it covers the stars, however, then it
seems incompatible with the third definition.
It might be argued that the second and third definitions are not meant to
be equivalent on the ground that the "body with organs" mentioned in the
third definition is explicitly introduced in the text as a body of a more
restricted type than the "body which has life potentially" of the second
definition (412 a 27 - b 1). If this were so we could take the second
definition, which covers the stars, as the accurate one and regard the third
as covering not all of the living but only a certain part of it. But the third
definition is said to mention "something common to every soul" (412 b 4).
The fourth definition introduces further problems. It apparently says
that any natural body which has an internal source of patterned change is
ensouled. But in the Physics (192 b 9-23) Aristotle claims that all the
familiar natural bodies have an internal source of patterned change. (Cf.
De Caelo 268 b 27, ff.). So on his definition rocks would seem to be alive.
And Aristotle would deny that rocks are alive (De Anima 412 a 13-15).
Some will urge that this fourth claim is not a definition, that it only gives a
necessary condition for being an ensouled body and no more. But it must
do more to play the role Aristotle gives to it in its context (412 b 10-17). He
argues that the thing that keeps an axe from being alive is that it doesn't as
an axe have the kind of natural body that engages in its proper motion -
chopping - in the cgurse of nature from some internal impulse. But rocks
do engage in their proper motion under internal impulse in the course of
nature (Physics 192 b 12, ff. at b 18). So the argument would seem to
require that they are alive. Even if we treat the fourth claim as giving only a
necessary condition for being alive, moreover, that still creates problems.
For, again, the stars are alive and, hence, ensouled and they do not engage
in any proper natural movement under internal impulse (De Caelo 290 a
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27, ff., 291 b 13). On this reading, furthermore, the definition would
require that nothing kept alive, as we say, by external artificial means can
really be alive, even if it continues to engage in all its proper life functions.
This would not only be an unfortunate thing for Aristotle to say, it would
put the fourth definition in conflict with the second and third. On those
definitions, it is enough for something to be alive that it engage in organic
life functions, whether with external or artificial assistance or not.8 We
might try to treat the fourth claim as giving only sufficient conditions for
being ensouled. The definition could be read as saying that soul is the form
of a natural body of the type which has an internal source of change, bul
perhaps of another type as well. But this interpretation, besides apparently
making rocks alive, would seem to spoil Aristotle's argument. If something
with another sort of body than the one mentioned can be ensouled, how
can the fact that an axe doesn't have that sort show that it's not ensouled?
Aside from these problems it is worth reviewing the old troubles mentioned
earlier which bear on all the definitions. In the very chapter where
these definitions occur, and in many other places, Aristotle claims that
some of the parts, that is some of the life functions, which make up the soul
are separable from the body since they are not the actualities of any body
or bodily organ (413 a 6-7).9 This seems to be ruled out in advance by all
the definitions, since any non-bodily entity which exercised any one of the
life functions (as the intellect does, 430 a 17-22) would have to be alive
(413 a 22-25)10 and hence ensouled (a 21-22). All of the definitions seem to
rule out the possibility that anything other than a natural body can be
ensouled or, hence, alive. The third definition, which supposedly mentions
something common to every soul, is especially problematic in this regard
since it is later explicitly claimed that "the soul which can think" (i] VOqTLXyL
[iuxid) is connected with no organ (429 a 22-29).
Aristotle also claims at the end of De A nima II, 1 that it is not yet clear
whether the whole soul11 of a living thing is the source of the activity
(6v?eXVXeLa) of its body as a sailor is the source of the activity of a ship
(413 a 8-9) - apparently leaving the door open to various forms of dualism.
Since he has just said that, given the third definition, "it is unnecessary to
inquire further whether the soul and the body are one" (412 b 6, f.), it is a
long-standing puzzle why Aristotle should make this remark.12
The prime mover gives rise to the final problem. It is alive and is, hence,
an ensouled entity (Metaphysics 1072 b 13, ff., cf. De Anima 402 b 5-8). But
the life function of the prime mover does not belong to any natural body
and is, afortiori, not the first actuality of any body.
The standard ways out of these difficulties involve attributing to Aris-
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totle inconsistency, change of mind, or mystery-making.13 But the inconsistency,
if such there be, is so bald that it is hard to see how Aristotle could
have failed to face it. And the hypothesized change of mind on Aristotle's
part is unacknowledged and has been hard to establish in any convincing
way.14 So solutions depending on these things have not been satisfying.
And it seems too much out of character that Aristotle should simply have
regarded the whole matter as an impenetrable mystery for that proposal to
be satisfying.
4. Do the remarks which Aristotle makes at the beginning of De A nima
II, 2 about various types of definition and about the defects in the account
of the soul in II, 1 help us to more satisfactorily resolve any or all of these
difficulties?
As we saw earlier, the definition, or definitions, of the soul in De A nima
II, 1 are implied by II, 2, 413 a 16, to be like conclusions (OuuR%ep&ixlrx).
That word is used in Posterior A nalytics II, 10 to describe one of the three
types of definition discussed there (94 a 7-9, 13-14). This type of definition
is contrasted both with the indemonstrable account of what something is
and with the syllogistically based account of what something is.'5 The third
type of definition,16 and hence the sort we are dealing with in De Anima II,
I, is the so-called nominal definition - the account of what a name signifies
(93 b 30).'7 What implications of this result are relevant for our purposes?
A nominal definition is the account of some entity or phenomenon
which we have at the initial stages of inquiry before we have an account of
its essence. The definition encapsulates the central items of information
about an entity which we have at a given pre-terminal stage.'8 These
central items of information'9 will, in Aristotle's view, typically concern
explicable features of the entity under investigation. So he characterizes the
definitions which display these features as "conclusions"(avRnpep&u-
iu,rr).20 There are, for Aristotle, two characteristic types of definition
which function as conclusions of syllogisms - those which exhibit a feature
(but not the whole) of the essence of the entity defined, and those which do
not exhibit even an element of the essence but do exhibit some proper (xLO'
o0'r6) feature which is explicable by reference to the essence.2' The first
type will exhibit a feature necessary but not sufficient for the presence of
the thing. The second will, characteristically, exhibit a feature sufficient
but not necessary for the presence of the thing.22
Aristotle takes it that nominal definitions signify a kind and delineate
the reference of the name of a kind.23 How do they do this when they only
exhibit features necessary or sufficient for membership in the class denoted
by the name of the kind but not both? Aristotle holds that grasping a
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nominal definition involves a knowledge of the existence of members of
the class in question24 and that the definition itself involves an implicit
reference to the most familiar actual instances of the kind defined.25 The
definition identifies the kind as the one to which those actual instances
belong and the membership of the kind as whatever has the same essence
as those instances.26
Given this, both types of nominal definitions do give necessary and
sufficient conditions of a sort for being instances of the kinds they define.
But they do not do this by exhibiting general features of those instances,
possessed by them as instances of their kinds, which are necessary and
sufficient for belonging to those kinds. Instead they do so by means of a
reference to the essence of certain actual familiar objects, an essence whose
content is not spelled out in the definition but whose possession is
necessary and sufficient for membership in the kind defined.
5. With this material in hand we can now return to the De A nima to see
what light is shed on the account of the soul which we find there. As we
have already seen, the famous definition of the soul in II, I is a nominal
definition. The use of the term 'uuv'rrpwuvx' (413 a 16, 18) to describe it
makes this clear. But what kind of nominal definition is it, one that exhibits
a necessary condition of soul or one that exhibits a sufficient condition? I
want to suggest that it is a nominal definition of the latter type: It points to
the most familiar (qvepavrpTa) instances of soul by means of a description
which exhibits only sufficient conditions for being an instance of soul, and
defines the soul as the generic form possessed by those instances.
The evidence for taking the nominal definition to be of this type is of two
sorts, direct textual evidence and more general inductive evidence. The
more general inductive evidence is, perhaps, the more striking, so we may
begin with it. If we understand the definition(s) of soul in De A nima II, 1 in
the way suggested, then the various problems which we have mentioned
concerning the definition(s) can all be resolved, and Aristotle's remarks in
De Anima II, 1 can be seen to be consistent with all of his doctrines
mentioned elsewhere.
The first of our worries about the definitions in II, I had to do with
whether they are extensionally equivalent. It seemed to us doubtful that
they are, but we were not reading the definitions in a way it is open to us to
read nominal definitions. The definitions of II, 1 are equivalent if they are
read as nominal definitions which exhibit sufficient conditions for belonging
to the kind defined. On such a reading the second definition will
say that soul is that generic first actuality possessed by those (actual
familiar cases of) natural bodies primed for certain life functions (which we
264

ecognize as ensouled).27 It will not say that these (familiar) bodies are the
only ones which have that actuality but rather that that actuality is the one
which they have. The third definition will say that soul is the generic
actuality possessed by (the actual familiar cases of) natural bodies with
organs (which we recognize as ensouled). Since the familiar bodies which
are primed for the familiar life functions are, at least in part, the same as
the familiar bodies with organs, the two definitions will be extensionally
equivalent. The fourth definition will say that soul is the generic form
possessed by those (actual familiar cases of) bodies with an internal source
of their activity (which we recognize as ensouled).28 Here the familiar cases
are again, at least in part, the same as for the other definitions. Since the
generic form of each of these groups of entities is the same, these
definitions will all be extensionally equivalent. Given this we cannot say
that the stars or the microorganisms without organs conform to the second
definition but not to the third. For the third does not say that only entities
with organs are ensouled. It says, merely, that only things with the same
generic actuality as certain familiar bodies with organs are ensouled. Nor
can we say that the fourth definition requires that rocks are ensouled. It
does not say that every natural body with an internal source of its activity is
ensouled. It says only that things which have the same generic essence as
the most familiar cases of self-moving bodies are ensouled. And this need
not, and in fact does not, include rocks.29 For similar reasons the stars do
not have to be self-moved to be alive; and entities whose life is maintained
artificially can still live - providing their essence is of the right generic
type. The definitions of II, I do not tell us directly what that type is, so they
do not settle these matters.
Earlier we noted difficulties in the way of treating the definitions as
exhibiting only suffitcient conditions for the presence of soul. As the sufficient
conditions are treated in Aristotle's nominal definitions of the type
we are considering, however, those difficulties no longer face us. The third
definition of the soul, as the first actuality of the most familiar cases of
natural bodies with organs, is said to mention "something common to
every soul." It is clear that it cannot do this if it only gives straightforward
sufficient conditions for the presence of soul. But on Aristotle's way of
construing nominal definitions which exhibit sufficient conditions it does
give something common. It identifies the generic form common to all
ensouled things. For Aristotle, any nominal definition identifies the kind
that its corresponding real definition displays (Posterior A nalytics 93 b 38
- 94 a 2).
Treating the fourth definition in the way suggested, moreover, does not
265

spoil Aristotle's contention that axes are not alive. Since the definition does
identify the generic kind to which all ensouled things belong it can be used
to rule axes out of that kind. Since it only exhibits sufficient conditions for
belonging to the kind, an argument that axes are not alive which was based
on it would likely not be very convincing even if sound. But Aristotle does
not in fact use it to argue that axes are not alive. When he discusses the axe
(412 b 10, ff.) he is only illustrating his contention that soul is the generic
form of (among other things) a special type of body - one other than the
type the axe has - and not arguing.
The reading of the definitions in II, 1 proposed here also provides us with
a simple way to resolve the worries over the conflict between those
definitions and the various claims which Aristotle makes concerning the
separability of the intellect from the body. The definition in II, 1 - in any
of its forms - does nothing to rule those claims out. If a functioning
intellect has the same generic type of actuality as familiar functioning
organic entities, independent of any attachmen to any body, then it is alive
and ensouled - and it is so according to the definition. The prime mover
too will count as a case of a living and, hence, ensouled entity, according to
the definition, since the actuality of the prime mover is of the same generic
type as that of the most familiar ensouled entities.
Given this understanding of the definition of II, 1, moreover, we cannot
claim that on that definition the mind-body problem does not arise. The
claim made at the end of I1, 1 that nothing up to that point has ruled out the
possibility that the soul is the actuality of the body as the sailor is of the ship
is compatible with what has gone before, understood in its natural dualistic
sense. The definition does require that as a whole the soul of the most
familiar ensouled things, including sailors, is incapable of its full functioning
apart from its body -just as the sailor is incapable of functioning as
a sailor apart from a ship. But since the definition does not of itself require
that every functioning soul be embodied, it by itselfleaves it open that most
of the life functions of even the familiar ensouled things can go on disembodied
- just as most of the psychic functions which a sailor employs in
sailing can go on apart from any ship.
This constitutes the general inductive evidence for the reading of the
definition of the soul in De Anima II, 1 proposed here. If it is a nominal
definition of the sort proposed, then we are no longer faced with inconsistencies
between different works (Metaphysics XII, and De Anima II) or
between different books of the De Anima (II and III) or within a single
chapter (II, 1) of the De Anima.
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6. We need now to look more closely at the text to see what direct
support it offers for our reading of the definition.
What we should be given in De A nima II, 2, ff. according to the opening
sentence of that chapter, is a new account of soul which stands to the
account of II, 1 as explanation to fact (IT'ra to O"Tl) and as reason to
conclusion (a'L'Tov to oavIepacvia). So we should expect to find a new
account from which the old account is somehow derivable. If we can find
such a new account that should help us to understand what form the old
account has in Aristotle's view.
The conclusion of II, 2 is that a certain account of soul has been
demonstrated. The conclusion reads: "It is therefore evident, from these
considerations, that the soul is a certain type of actuality and defining
principle (Xoyos) of that which has the capacity for life" (414 a 27-28,
reading TOLOVTOv at a 28 as at 412 a 21). This definition of soul which is said
to have been established omits explicit reference to the body altogether,
unlike the earlier definitions in II, 1. But according to this definition soul is
the form of that which has a certain capacity or potentiality and Aristotle
has just said (414 a 16-17, 25-27) that what has a given potentiality is
always matter of a certain sort.30 So this definition says, implicitly at least,
that the soul is a certain type of actuality or form of a certain type of living
body. So understood, the definition is, in its general import, equivalent to
the definitions of II, 1.
Is there, then, any other general definition from which this definition is
derived over the course of II, 2? The most prominent general proposition
about soul offered in the chapter is the one introduced at 413 b 11-12:
"Soul is the source (&pXA) of and is delimited by the life functions, such as
nutrition, sensation, thought and motion." This proposition is the first
account of soul at which Aristotle arrives after having begun, at 413 a 20,
his search for a new definition. And the pattern of the discussion following
this new account is what we would expect given the interpretation of the
opening lines of 11, 2 defended earlier. The new account of soul is higher up
in the order of explanation than the account of II, 1 since from it that
earlier account is derived, as follows:
(1) Soul is the source (&pyA) of and is delimited by any one or more of the
life functions - nutrition, sensation, thought and motion (413 a 22-25,
withb 11-12).
(2) The defining life function of plants (413 a 25-31) and that of animals
(b 1-4) - though probably not all life functions (b 24-29) - are the
functions of an appropriate sort of body (b 27-29).
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(3) Our soul is also "that whereby" we have primarily the defining life
functions which we have (414 a 12-13, from 414 a 4-12).
(4) These functions are also the functions of an appropriate sort of body
(414 a 19-25).
(5) That whereby something has its characteristic functions primarily is its
form or actuality (from 414 a 8-10 with a 14-19).31
(6) So soul is the actuality of the sort of body which has the capacity for
life functions (414 a 27-28).
Laying out the derivation in detail reveals that the conclusion, the old
definition, must be understood in a special way. It does not say that every
type of soul is the actuality of a certain type of body - in which case being
embodied would be a necessary condition of being a soul. It cannot say that
in view of the content of (2) and of the form of the derivation. In the
derivation three types of soul - plant, animal and human - are surveyed
and found to be the actualities of certain types of bodies. But, it is, at the
very least, said to be a puzzle (?rropia) and to be unclear (ovi qxvepov)
whether there are types of soul which are entities of a different sort (413
b 13-16, 24-27).32 So the conclusion which states only what is clear from the
foregoing discussion (cpavep6v ix TOV'TV), cannot rule out such types of
soul. The conclusion must be read as saying, then, that soul is the generic
actuality certain cases of which are, necessarily, embodied. So the conclusion,
the definition of II, 1, is a nominal definition of the sort that
exhibits sufficient but not necessary conditions for being an instance of the
entity it defines.
Consider now the new definition at (1). It says merely that soul, generally,
is the source of each of the life functions or each group of them that
subsist together. It openly affirms that anything which exercises one or
more of these life functions is ensouled whether the exercise requires the
operation of some bodily organ or not. So the character of the new
definition of II, 2 and the details of the derivation of the definition of II, 1
(or its nominal equivalent) from the new definition both allow our
hypothesis concerning the nature of the definition of II, I and confirm it.33
The new definition of II, 2 stands, subject to a qualification to be mentioned
below, as real definition to the nominal definitions of II, 1.34
7. This interpretation of the definition of the soul in II, I is supported by
another passage in II, 2. Aristotle offers there an example which illustrates
the way in which the definition of II, 1 is defective.35 The example is a
definition of a squaring or quadrature (TEpTywvLuRi6s) as "an equilateral
rectangle equal (in area) to a given figure with unequal sides" (413 a
17-18). This definition points to a certain very familiar case of squaring36
268

ut it exhibits a sufficient and not a necessary condition for a squaring. It
focuses only on the squaring of plane figures and, as Aristotle was aware,
not only plane areas can be expressed as the squares of some magnitude
but also numbers.37 Aristotle offers as the correct definition of squaring,
"finding a mean proportional" (413 a 19). This definition is repeated in the
Metaphysics (996 b 20-21) as a definition of squaring generally ('rb
TE'rpaycvLCtLv) without any restriction as to type of magnitude. And it
covers numbers as well as plane areas.38 In the Metaphysics this definition
of squaring, "finding a mean proportional," is given as a paradigm of a
statement of the essence (ovaia and # oTn) of something (996 b 10-12). So
if this is an accurate illustration of the character of the new definition of
soul in II, 2, as Aristotle intends it to be, that definition must give the
whole of the essence of soul and the definition of II, 1 cannot give even a
part of the essence. Given this there is, again, only one type countenanced
in Aristotle's theory of definition to which the familiar definition of II, 1
can belong, and that is the type to which we have assigned it.
8. Further light on the character of the definitions of II, 1 can be gotten
from closer attention to the argument which leads to the first definition of
soul there. That argument is similar in structure to the one we have just
been considering. It concludes that soul is substance in the sense of form,
being the form of a natural body which has life potentially (412 a 19-21).
The curious thing about this conclusion, which is the first definition of II, 1,
is that it focuses, like 414 a 12-13, on a special range of life functions. In it,
and in its successor, 'life' has the special signification introduced at 412 a
14-15: "nourishment, growth and decay through itself." So the first
definition at 412 a 19-21 says that soul is the form of those natural bodies
which have the capacity for just these elementary life functions. But it has
to identify the generic form of, at least, all organic bodies (412 a 27, ff.)
and, hence, to at least identify the generic form which some such bodies
possess by having other life functions as well as these (cf. 413 b 11, ff.). To
do this the initial definition has to say that soul is the generic form which
belongs to those familiar bodies which have the basic functions of nourishment,
growth and ageing, leaving it open that the possession of soul can
involve the capacity for other functions than those.
Once we understand this we can see what the progression from
definition to definition in II, 1-2 is. The first two definitions of soul, as the
form or first actuality of a natural body which has the capacity for
nutrition, growth and ageing, focus on entities which possess one special
type of soul. This is the type "most common" to living things (415 a 23-25),
a fact which makes the first two definitions appropriate starting points.
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They characterize soul generally as the generic form possessed by entities
of the special type in question. The third definition of soul, as the first
actuality of a natural body with organs, focuses on a wider range of entities.
Entities characterized by any of the special types of sould defined by
reference to collections of organic functions are in focus in this definition.
The fourth definition speaks of soul more generally as the type of form
possessed by a certain sort of natural body with an internal source of its
activity. This definition focuses on certain natural bodies which engage in a
certain range of activities but does not tie those activities down to organs.
The new definition of II, 2 marks another stage in the process of generalization.
It defines soul as the generic form of the type possessed by whatever
engages in any life function. Here the functions are neither tied down to
organs nor tied down to body.
9. Having attended to those features of the text which support the
reading of the definition of II, 1 offered here, we should consider those
features which might be thought to go against it. One of these has already
been alluded to. At 412 b 4-6 and b 10 Aristotle speaks of one variant of the
account of soul in II, 1 as an account which "mentions something common
(TL XOLV6V) to every soul" and which "says what soul is in general (xa0o-
Xov)". As we have seen, however, these remarks are not inconsistent with
the interpretation offered here.39 The generic form of the familiar natural
bodies with organs belongs even to the separate intellect and to the prime
mover.
Aristotle also says at 412 b 6-9 that it follows from his account of soul
that we do not need to inquire whether "the soul and the body are one,"
since an actuality and that of which it is the actuality form a unity in the
strictest sense. This does require that any type of soul which is the actuality
of a particular body is not separable in toto from that body and that that
body is not separable in toto from that soul. But it does not require that no
faculty or faculties of such a soul are inseparable from the composite to
which they are attached (413 a 3-7), nor that such a faculty could not when
separate engage in some life function and be, hence, alive and ensouled
(413 a 20-25).40 That "the soul and the body are one" no more requires that
every ensouled thing is embodied than it requires that every material object
is ensouled. The phrase "the soul" is no more general than its companion,
"the body." And the phrase "the body" refers not to bodies in general but
to the special bodies of certain particular things (412 b 6-8, 11-17). In the
Metaphysics, in language which echoes that in the De Anima, Aristotle
claims that in general "the proximate matter and the form are one and the
same thing" (1045 b 18-19). The unity in view there is just the sort which
270

obtains between soul and body (1045 a 23-33 with 1075 b 34-37). But
Aristotle is not claiming there that every form is identical with some
proximate matter. He denies that in the very place where he speaks of the
form and the matter as one (1045 a 36, f.).41 It is "the proximate matter
and its form" which are one (cf. 1041 b 7-9). So when Aristotle speaks in
just the same way about soul and body he need only be talking about
embodied souls and ensouled bodies. In the subsequent discussion the
terms "soul" and "body" are used in a similarly restricted way to refer only
to animal soul and body (412 b 27 - 413 a 3 with 412 b 22-25).
Aristotle also remarks, at 414 a 19, ff. that:
Those who take it that the soul is neither independent of body nor a type of body are
right. It is not a body but a type of thing which belongs to a body and, therefore, it
exists (in&pXEL) in a body - a body of a particular sort.
This too might be taken to go against the interpretation proposed here. But
Aristotle is again not taLking about all cases of soul. He is using the term
"the soul" here in the familiar sense of "the human soul," as the context
makes clear. The "soul" which Aristotle has just been discussing is "that
whereby we live and perceive and have understanding primarily" (414
a12-13). This is only one in the series of types of soul which Aristotle is
surveying in De A nima 11, 2- the human soul. Aristotle wants to show that
this soul is, like the others surveyed there, "a type of thing which belongs to
a body."42
Finally, there is Aristotle's suggestion that the intellect and the faculty
of theoretical reasoning, being separable from the body, constitute "a
distinct kind of soul" (4vxijs y?VOS '?'TEpov, 413 b 26). Some have read this
remark to mean that the study of this faculty of soul belongs to a different
science altogether than the one whose subject is delimited by the general
definition of soul in II, 1.43 If that were so then we would not have to worry
over how to make the definition of II, 1 fit the separate intellect. However,
Aristotle treats this faculty of soul as one of the parts of the generic entity he
is discussing in the very place where he refers to it as a distinct kind of soul.
(See r6t XoLrr &0pupa iris 4vxips, 413 b 27-28). He treats it in the same way in
DeAnima III, 4 (429 a 10, f.; cf. a 23) and speaks of it there as a type of soul
(i voqrIxi [+vx ], a 28; cf. De GenerationeAnimalium 736 b 13-16). If this is
so then the definition of II, 1 which mentions something common to every
soul must cover it. And the only way allowed by Aristotle to read a
definition which makes it intelligible how the account of II, 1 can mention
something which belongs to the separate intellect is the way defended
above.
10. It remains for us to deal with a rather technical problem concerning
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the adequacy of the new definition of soul in I, 2. Does the claim at the end
of II, 3 that the most appropriate account of soul (Xoyos oLxEL6TxTos . . .
'nep'p ivXiAs, 415 a 13) is a serial account of each of the distinct life functions,
spoil in any way the results of II, 2? In particular does it show that the new
account of soul in II, 2 does not genuinely give the explanation (t'iTLov) of
the account of II, 1 or the essence (OL'Ta) of the actuality which is soul
according to the definition of 11, 1. A problem arises because the account,
in sequence, of the special faculties is said to be most proper not as an
account of the special faculties but as an account of soul simply (415 a 13).
This strongly suggests that the general account of II, 2, though it explains
the account of II, 1 in a way, is still not a full real definition or account of
the essence of anything. And this is in fact required by other evidence.
According to the Posterior A nalytics, the true explanation of some fact (oTL)
is supposed to give the essence of that of which the fact holds (90 a 5-15,
93 a 3-9). And according to the De A nima no general account which covers
several species of some genus can give the essence of anything (414 b
25-27). The doctrine of the Metaphysics (1030 a 6, ff.) that only ultimate
species have definitions which, strictly speaking, give the essence of anything
is clearly in play in the De A nima. And given the doctrine of the
Metaphysics, we must conclude that the definition of II, 2 does not, strictly
speaking, stand to the definition of II, 1 as account of essence to account of
fact. But the definition of II, 2 is in fact only put forward as one which will
suffice for the time being (413 b 11-12). Did Aristotle believe then that this
definition only leads us in the direction of the most proper explanation of
the definition of II, 1, and that the full account of the particular faculties
would provide one with such an explanation? That seems the natural way
to make the conclusion of II, 3 consistent with II, 1-2. It is easy to see how a
new serial account of soul as the source (ap)i') of each of the various
special faculties in sequence would serve to establish the claim of II, 1 that
soul is the generic actuality certain cases of which belong to a special sort of
natural body. For many of those faculties will be explicitly shown by this
account to constitute, individually or collectively, types of soul which are
capable of existing only in such a body.
We can, however, still speak of the definition of II, 2 as giving, so far as is
possible, the full essence or the real definition of the genus of each type of
soul - remembering that no such genus can, strictly speaking, have an
essence or, hence, a real definition. The definition of II, 2 does give a full
explanation (ai'TLov), in the sense of that term employed in the Posterior
Analytics, of the fact (orL) stated in the definition of II, 1. (The doctrine that
no genus can have an essence is not found in the Analytics.) But the new
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doctrine of the Metaphysics requires us to say that the new definition can
only in a secondary way give the essence of anything (1030 a 17, ff.). This
qualification leaves our earlier results unaffected.
The upshot of those results is that the definition of the soul as the form of
the body (in any of its variants) should not be understood in the usual way.
Correctly understood it does not entail that every soul is embodied. It does
entail that certain types of embodied forms are souls but it does not tell us
which types those are. So, as far as the definition goes, not only the intellect
but other faculties of soul as well might exist unembodied or disembodied.
Aristotle does not believe that many, if any, of these other functions can
exist unembodied but that is a matter which he undertakes to prove by
showing that these functions require the operation of specific bodily organs
(see 413 b 13-29). The matter is not settled by the definition.
It follows from this that in Aristotle's view the mind-body problem is not
one that can be settled on what we would call conceptual grounds. The
definition of soul in II, 1, being a nominal or semantic definition, is an
account by reference to what is more familiar to us. As such it explicates
what the common understanding of the notion of the soul is (Topics
141 b 3-14). But this common understanding focuses on certain special
cases of soul and does not incorporate any fully general description of what
a soul is. So one cannot say in general on the basis of this account of the
ordinary concept of the soul what the relation between soul and body is.
11. We may conclude by noting certain implications which the results of
ur study of Aristotle's definitions of the soul have for the interpretation of
Aristotle generally.
At the end of De A nima II, I Aristotle speaks of his initial account of the
soul as a sketch "in outline" (Tv$vi). As we saw at the outset, he characteristically
uses this expression to describe initial accounts of the sort which
are "more intelligible to us" and which give only derivative facts about
some entity rather than its essence." Other passages ally accounts described
in these latter ways with nominal definitions. In Physics I, 1 (184 a
16 - b 14) an account which is more intelligible to us is said to be of the
same sort as a nominal definition. And in De Anima II, 2 (413 a 13, ff.) an
account which gives only a fact is said to be like a "conclusion" or nominal
definition. This makes it apparent that an account "in outline" is likely to
have important similarities, at least, with one or another type of nominal
definition.
A striking proportion of what Aristotle says in his works - about everything
from the syllogism to substance to the highest good - is qualified by
use of the expression "in outline" and the related expressions applied in De
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Anima II, 1-2 to the initial definition of the soul.45 This highlights the
importance of the discussion of nominal definition in the Posterior Analytics,
since that is the one place where Aristotle explains in a full way what
at least one sort of account of this type is like. It also indicates that special
care may need often to be taken not to attribute to Aristotle views stronger
than those to which he is actually committed - when, as in the case of the
famous definition of the soul, what he says only describes the object under
discussion "in outline."46
Rutgers College, Rutgers University
1 The standard contemporary attempts to deal with the problem are those of W. Jaeger,
who argued that the dualistic doctrines are inconsistent with the anti-dualist definition
and constitute an inheritance from Plato which Aristotle never abandoned (Aristotle, 2nd
edn., Oxford, 1948, 217-219, 332-34); F. Nuyens, who supposed that the problematic
doctrines while not inconsistent with the definition constituted with it for Aristotle a
mystery whose threads he could not unravel (L'tvolution de la Psychologie d'Aristote,
Louvain, 1948, Ch. VII, especially 317-318); and W. D. Ross, who argued that the
dualistic doctrines belonged to an earlier phase of Aristotle's thought and were abandoned
by the time of writing of De A nima II ("The Development of Aristotle's Thought,"
Proceedings of the British Academy, 43 (1957) 65-67). For the standard older views, see the
discussion in R. D. Hicks, Aristotle, De Anima (Cambridge, 1907), pp. lxiv-lxix.
2 r4vrc and &xpl0s are standardly contrasted with each other. See H. Bonitz, Index
Aristotelicus (Berlin, 1870), p. 779. Physics 184 a 23-26 shows that xao6Xou is sometimes
used like rimy and contrasted with W' &xpOEiaS. See also Prior Analytics 46 a 10, ff.,
a 28-30.
3 Cf. De A nima 402 b 16, ff The account which gives the akrla is the one which gives the
genuine ri bL. This is presumed in the illustration at 413 a 17-20 and is required by the
language, as we shall see below.
4 Two other ways of reading the opening remarks of II, 2 deserve consideration. (1)
Aristotle is announcing the method which he is about to follow - beginning with matters
which are "clearer to us" than the definition of II, I (namely, the accounts of the
particular faculties of soul) and working up inductively to a new account which is an
improvement on that definition. (See R. D. Hicks, op. cit., p. 322. Hicks was following
Simplicius, in De A nima, 96-97 Hayduck). But Aristotle does not produce a new account
of soul at the end of his discussion of the special faculties. At the end of II, 2 we have the
old definition reaffirmed (414 a 27-28; see below Sec. 6); and there is no new definition
after that. And the accounts of the special faculties are not and cannot be derived from
any new fully adequate general account of soul as they would be if they were accounts of
soul which are "clearer to us." (Such accounts stand to the fully adequate account in the
relation of fact to explanation and conclusion to reason, 413 a 11-16). The relation is
rather the other way around (see Sec. II). (2) Aristotle is beginning again from an account
of soul which is more obvious to us than the definition of II, I and working from that to
establish inductively the old definition which is itself "more intelligible in the order of
explanation." (So, apparently, Aquinas, in De Anima, Sections 245, ff. Pirotta; but see
Section 244.) But the definition of II, I is itself an account "in outline" ('rimy), and
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Aristotle never applies this language to a fully adequate account. As shown above, an
account 'rimr has the features of an account that is "clearer to us" in contrast with one
which is "more intelligible in the order of explanation" and one which states the facts
about some subject without giving the essence in contrast with one that gives the essence.
Moreover, the only new general account of soul offered after II, 1, at 413 b 11-13, is not
derived by Aristotle, as it should be on this reading, from the account of II, 1 (nor can it
be, since it covers the &pxij of the functioning separate intellect and the account of II, I -
taken as a fully adequate account - does not). Again, it is the other way around (see
Sections 5-8 below). Also, it would be quite uncharacteristic of Aristotle to start an
inquiry with an account which is better known absolutely and then take up an account
which is better known to us. This goes against his preaching and his practice (see, e.g.,
History ofA nimals 491 a 7-14). The reading proposed here accommodates the description
of the definition of II, I at 413 a 9-10 and fits the pattern of the discussion of II, 2. It is
closest to the reading of G. Rodier (Aristote, Traite de l'Ame Paris, 1900, v. 2, 188-191),
though it differs from his in various important respects.
5 This remark is not normally taken as one of the definitions of the soul in De A nima II, 1.
But the phrase "of that sort which has . . ." (TOLOV8 FxoVros . . ., b 16-17) specifies the
sort of body which ensouled things, as opposed to axes, have. It fills out what the "certain
sort of body" (roovw& aqLsa) of b 11 is. And soul is xa%Xov the essence of that sort of body
(b 10-11). See, further, below on this.
6 See De Caelo 292 a 20 ff., b 28 f., 290 a 29 ff., 285 a 29. The rendering of owpa 6pyavLx6v
(412 b 5-6) as "a body with organs" is standard and 412 a 28 - b 4 strongly supports it.
Another possible rendering is "a body which serves as an instrument." (Cf. De Partibus
Animalium 642 a 14, ff.) Such a body perhaps need not have organs, but only serve as an
organ for, in the case in question, the performance of some vital function. So understood,
an amoeba would, perhaps, have a aupa 6pyavLxo'v. But Aristotle does not believe that a
living thing can perform active functions without organs which are heterogeneous parts
(De Partibus A nimalium 646 b 11. ff.). So the amoeba still poses a problem. And the other
problem remains. The stars do not use their bodies or any organ to move (De Caelo
290 a 29, ff.).
7 See 412 a 22-28 with 412 b 17-26 and 417 a 21, iff.
8 These same problems would arise on any attempt to treat the fourth definition as
referring to a special type of capacity for self-motion whose possession is necessary and
sufficient for the presence of life and soul. Cf. n. 30, below.
9 See also 408 b 18, ff., 411 b 15-19, 413 b 24-27, 430 a 17-23. This claim is found also in
the biological works; see De Generatione A nimalium 736 b 27-29, 737 a 7-10.
10 Metaphysics 1072 b 26-27 reaffirms that the activity of the intellect (vovs) is a form of
life (twi). And De A nima 29 a 28 speaks of the intellect as a type of soul (h VOq-TLX [iv 'Ix).
At 413 a 8 it is soul (sAvxh) simply, in contrast (9,r a 8) to its parts (a 6-7), that is in
question.
12
See G. Rodier, op. cit. for a concise report of the views of the older commentators.
13
See n. I above.
14
It is difficult to argue for an early date for De Anima III, 5 as Ross did (see n. 1), given
the anticipations of its doctrines in Il 1, 2. Ross himself dropped the suggestion in his
commentary (Aristotle, De Anima, Oxford, 1961, pp. 7-12).
15 The commentators are not clear on this. Hicks, for example (op. cit., p. 322), identifies
the definition which functions as conclusion with the type which displays the essence.
16
Some have tried to avoid this by introducing a fourth type of definition into Posterior
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A nalytics II, 10. This is contrary to Aristotle's assertion at 94 a I1 ,ff.(cf. 75 b 31-32) and to
other evidence, but it is enough for our purposes in this paper that the definitions of De
Anima II, I belong to the type called "conclusions." Here, and in what follows, the
discussion draws on the results of "Essentialism and Semantic Theory in Aristotle:
Posterior A nalytics 1I, 7-10," Philosophical Review, I 85 (1976); referred to below as ESTA.
On the point in question here see ESTA, n. 14.
17 This conclusion is confirmed by the other language used to describe the definition in
De Anima II, 2. The definition is said there to merely state a fact ('r bT&) about the soul
and not to specify the essence (j alrCat) which explains such facts. This language is used in
the Posterior Analytics to contrast nominal with real definitions (93 a 16, ff., 93 b 29, ff.).
The definition is also said to give an account of soul which is clearer to us but less
knowable in the order of explanation. This language is used to characterize nominal
definitions as opposed to other types at Physics 184 a 18, ff.
18
Posterior Analytics, 93 a 16-29 with 93 b 29-32 and 94 a 7-9.
19 The items can change from stage to stage; 93 b 7-14 at 12-14.
20 93 b38-94a9.
21
Some of these definitions give "something of the thing itself' (T axaroi,roe 'fp&yRaros),
i.e. an element of the essence of the thing, 93 a 22-24, 27-29 with 94 a 7-9; others give not
an element of the essence but only a feature by means of which we grasp the existence of
the thing and are pointed to (a knowledge of) the essence (vpbs [-T C8?vai] To Tv kaTL) due
to the fact that the feature is exhibitable in a conclusion derivable from the essence
(93 a 27-29, a 35-37; cf. De Anima 402 b 21-22). There is a third type of nominal
definition, one which mentions merely accidental features of the entity defined (93 b
29-37, cf. 93 a 24-26). But this type can only function as a conclusion of a syllogism or a
statement that something is (Tb bTL) in a secondary way (75 b 30-32). So this type is not in
play in De A nima II, 1.
22 See 84 a, 11, ff. for the two permissible types of conclusions of demonstrations. The
second type could, in principle, exhibit the inherence of a proprium in a thing but
Aristotle thinks that such conclusions are very rare (73 a 6-7, 16-20).
23 Nominal definitions are accounts of what some word or phrase signifies (0aiiwve),
93 b 29-32. And signification has two components, reference and a fixing on a kind. (See
the uses of ajo.clveLv at 92 b 26-34, 93 b 39-94 a 2 and ESTA, Sec. 7.)
24
93 a 16-29 with 93 b 29-32 and 94 a 7-9, and ESTA, Sec. 6. Cf. n. 26 below.
25
An example of the type of nominal definition which specifies a feature of the essence is
'Thunder(OpovTi)
is a certain type of noise in the clouds (4&pos'rs vrqGCv)' (93 a 22-23).
This definition does not say that any noise in the clouds would be thunder. It says that
thunder is that certain type of noise in the clouds, familiar actual instances of which we
recognize as thunder. It says, hence, that something is an instance of thunder if and only
if it belongs to the same kind as those familiar actual instances. An example of the type of
nominal definition which specifies a proper feature not a part of the essence is 'Eclipse is
the failure of the full moon to cast shadows when nothing visible is in the way' (93 a 36 - b
7). This definition refers us to familiar actual cases of eclipse by means of a description
which provides us with a sufficient condition for the occurrence of an eclipse. It tells us
that something is an eclipse if and only if it has the same essence or cause (adxiTa or &6rt1)
as those actual cases of inability of the full moon to cast shadows under a visibly clear sky
which we recognize as cases of eclipse. See ESTA, Sec. 9. For another definition of this
type see the definition of a citizen at Politics 1275 a 29-33 (with a 33 ff. at b 5-7).
26
The indefinite 'TLS' plays a crucial role in definitions of this type (see 93 a 21-24). It
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means "that certain familiar." This is made clear by an important passage in the Physics
(1, 1, 184 a 16 - b 14, at a 26, ff.) which reveals that initial (nominal) definitions in science
are accounts by reference to actual cases of the entity defined which are familiar to us.
These definitions focus by means of such a reference onto a certain familiar whole (QXov
n). See ESTA, Sec. 7.
27 Here and in what follows I make explicit in parentheses various features of nominal
definitions which Aristotle himself normally only brings out in theoretical discussions of
definition. See nn. 25-26, Sec. 7 below, and ESTA, Secs. 6-9.
28 In the fourth definition '"oLoa&' (412 b 16) functions as 'fIs' does in the nominal
definitions at PosteriorAnalytics 93 a 22-24 to indicate that it is a special sort of body that
is in question here (cf. 'roip,& a6paxn, b I 1) and not just any body with an internal source
of change. That sort is "the most familiar sort" with an internal source of change and it is
the function of the 'roLoo00' to signify this. (Cf. Metaphysics, 1035 b 16 and 1043 a 36,
where 'To&6a8E' and 'Tus' play, interchangeably, this role.) So understood the definition
does provide a sufficient condition.
29 It is not here assumed that Aristotle ever succeeds in adequately differentiating the
innate capacity for motion of living things, especially plants, from the innate impulse to
motion (Physics 192 b 18) possessed by al inanimate natural objects. See F. Solmsen,
Aristotle's System of the Physical World (Ithaca, 1960), 95-102. But the fourth definition
of soul leaves open the possibility of a solution.
30 This rules out the reading of 414 a 27-28 in J. Owens, "Aristotle's Definition of Soul,"
in R. B. Palmer and R. Hamerton-KeUy (eds.) Philomathes (The Hague, 1971), at n. 29.
31 Assuming the primacy of the actuality of a function to the function, as at 415 a 18-20.
This step in the argument is not explicit but it is easily supplied.
32 In fact Aristotle's claim at 413 b 24-27 is the stronger claim that "it is likely (Iotxe) that
the intellect is a different type of soul, and it alone is separable." That 'IOLXE' has this force
is clear from the parallel passage 408 b 18-29 (cf. 430 a 17-25).
33 It might be suggested that the definition of II, I is a nominal definition of the sort that
exhibits necessary conditions for the presence of soul. If so, then according to the pattern
at Posterior Analytics 94 a 3-9 the new definition of II, 2 would be a combination of the
old definition of II, I and what we have been calling the new definition. In that case the
correct new definition would be: Soul is the source (&p ii) of any group of the life
functions, which source is always possessed (as first actuality) by a natural body which
has life potentially. In this case each type of soul would have to be a function of some
natural body. But Aristotle denies having claimed this in the very place where he is
developing his new definition (413 b 13-16, 24-29). So his new definition can hardly have
this form.
34 "Source of life" (&PX. Tow iv,
413 b 11-13 with a 22-25) may seem rather thin and
commonplace for a real definition. But Politics 1275 a 38 - b I shows that genera of the
type to which soul belongs are very thin in content (cf. De A nima 414 b 28-32) and the real
definitions of entities of this type may be quite commonplace (see Politics 1279 a 25-27
with 1278 b 8-10, ff., and for the sort of definition of figure probably in view at DeAnima
414 b 20, ff., see Euclid, Elements I, Def. 14). The account of II, I may also seem rather
technical for a nominal definition. But even a relatively advanced account may still be
what is "familiar to us" and only nominal. (See the nominal definition of squaring at 413
a 16-19; cf. Politics 1275 a 29-34 and n. 25 above.)
35 Note that the new definition of II, 2 is not defective in this way - another reason for
not taking it to be the inferior definition in view at 413 a 11, ff. Cf. n. 4 above.
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36 The squaring of a plane rectilinear figure which has been reduced to a rectangle with
unequal sides. For the theorems which Aristotle has in mind in this connection see Sir
Thomas Heath, Mathematics in Aristotle (Oxford, 1949), 191-193.
37 See, e.g. Posterior A nalytics 76 b 8, and Heath, op. cit., 43-44.
38 To square, i.e. to find the square root of, a number is to find the mean proportional
between two factors which, multiplied together, yield the number.
" See above, Sec. 5. Physics 184 a 16, ff. at a 23, 25 makes clear that all nominal
definitions and all accounts from the point of view of what is more familiar are accounts
of something "in general" (x066ou). The infant's notion of woman as what mother is
contains an understanding of what a woman is xa(6Xov. It does mention a characteristic
common to all women - being not a mother but what mother is - but it only does this in
an indirect way. And this mention is indirect in the same way as that in the nominal
definition of II, I on the reading given here.
40 In view of this Aristotle cannot mean to say at 415 a 23-25 that nutrition is a faculty
belonging to all living things. He says that "the nutritive soul is the first and most common
faculty by which life belongs to all the things that have life, taken collectively, and is the
faculty most widely distributed over that collection; but not that it belongs to each
member of that collection. 434 a 22-26 covers only those things which "live, and have soul
from birth to death," i.e. with mortal things, as Aristotle's more careful statement of the
same point at 413 a 31-32 confirms.
41 Taking an essence ('ri iv elvaL, 1045 b 3, to be a form; 1032 b 1-2, with De Gen. et Cor.
335 b 35. Cf. 1037 a 1-2). The entities which consist of form without matter here are the
categories, but that does not affect the point at issue. Aristotle, moreover, describes the
essence of the prime mover (1071 b 19-21) and that of the separate intellect (De Anima
430 a 22-23) in the same way. The substance (ov'ai) of the intellect (408 b 19,430 a 18) is,
doubtless, substance in the sense of form (412 a 6-9).
42 Cf. Sec. 6 above. The view of 414 a 19-20 is attributed by Aristotle to certain of his
predecessors. When they spoke of the soul, as he points out, they were almost exclusively
discussing the human soul (402 b 3-5). Commentators agree that the view is closest to the
position discussed by Aristotle in the Eudemus and at De Anima 407 b 27, ff., and
defended by Simmias at Phaedo, 85 e ff. (414 a 22-25 seems to recall the deficiency in the
view discussed at 408 a 10, f.) Simmias was talking about the human soul and so was
Aristotle in the Eudemus (see W. D. Ross, Aristotle: Parva Naturalia, Oxford, 1955, pp.
3-5). Cf. Politics 1340 b 14-19. At De Anima 402 a 6-10 "soul" covers only animal souls.
43 See E. Zeller, Aristotle and the Earlier Peripatetics, Eng. tr. (London, 1897), 4.
44 See above, Sec. 2.
45 See Bonitz, op. cit., under 'T&wos', 'i'nro'runo0v', and yv6pitos and, in particular,
Metaphysics 1028 b 27-32 at 31-32, 1029 b 3-12; Ethics 1094 a 25, b 19-22, 1176 a 30-32,
1179 a 33-35.
" An earlier version of this paper was read to the Ancient Greek Philosophy Colloquium
(NYC). Many points in the paper have been improved as a result of the discussion on that
occasion and as a result of later discussion with John M. Cooper.
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