Chapter IX: Nature and Person (1)

70. SOME DIVISIONS OF SUBSTANCES.—In the preceding chapter we discussed the nature of substance and accident in general, and the relation between a substance and its accidents. We must next examine the category of substance more in detail, terminating as it does in the important concept of personality or person. This latter conception is one which must have its origin for all philosophers in the study of the human individual, but which, for scholastic philosophers, is completed and perfected by the light of Christian Revelation. We shall endeavour to show in the first place what can be gathered from the light of reason about the constitution of personality, and also briefly to note how Christian Revelation has increased our insight into the perfections involved in it. As leading up to the concept of person, we must set forth certain divisions or classifications of substance: into _first_ and _second_ substances, and into _complete_ and _incomplete_ substances.(277)

(_a_) The specific and generic natures of substantial entities do not inhere, like accidents, in individual substances; they constitute the essence of the latter, and hence these _universals_ are called substances. But the universal as such does not really exist; it is realized only in individuals; in the logical order it pre-supposes the individual as a logical subject of which it is affirmed, a _subjectum attributionis seu praedicationis_. Hence it is called a _second_ substance, while the individual substance is called a _first_ substance. Of course we can predicate attributes of universal substances, and use these as logical subjects, as when we say “_Man_ is mortal”. But such propositions have no real meaning, and give us no information about reality, except in so far as we can refer their predicates (“mortal”), through the medium of their universal subjects (“man”), back ultimately to the individual substances (John, James, etc.) which alone are real, and in which alone the universal (“man”) has its reality. Hence the individual is, in the logical order, the ultimate and fundamental subject of all our predications. And furthermore, the individual substance cannot be used as a logical predicate of anything underlying itself, while the universal substance can be so used in relation to the individual.

In the ontological order, of course, the universal substance is individualized, and, as individual, it is the subject in which all accidents inhere, their _subjectum inhaesionis_: the _only_ subject of many of them, and the _remote_ or _ultimate_ subject of those of them which inhere _immediately_ in other accidents.

Thus while in the ontological order all substances, whether we think of them as universal or as individual, are the ultimate subjects of inhesion for all real accidents, in the logical order it is only the individual substance that is the ultimate subject of attribution for all logical predicates. Hence it was that the individual substance (τόδε τί ὄν), vindicating for itself more fully the rôle of subject, was called by Aristotle οὐσία πρώτη, _substantia prima_, while he called the universal, specific or generic substance, οὐσία δεύτερα, _substantia secunda_.(278) These are, of course, two ways of regarding substance, and not two really distinct species of substance as genus. The distinction between the _membra dividentia_ is logical, not real.

The perfectly intelligible sense in which Aristotle and the
scholastics designate the universal a substance, the sense of
moderate realism, according to which the universal constitutes,
and is identical with, the essence of the individual “person” or
“thing,” is entirely different from the sense in which many
exponents of modern monistic idealism conceive the universal as
the substance _par excellence_, the _ens realissimum_,
determining, expressing, evolving itself in the individual
phenomena of mind and of nature, which would be merely its
manifestations.(279)

(_b_) The divisions of substance into spiritual and corporeal, of the latter into inorganic and organic, of these again into vegetative and animal, and finally of animal substances into brute animals and human beings,—offer no special difficulties. All purely natural or rational knowledge of the possibility and nature of purely spiritual substances is based on the analogy of our knowledge of the human soul, which, though a spiritual substance, is not a pure spirit, but is naturally allied with matter in its mode of existence. The individual human being offers to human experience the sole example of the sufficiently mysterious conjunction and combination of matter and spirit, of the corporeal mode of being and the spiritual mode of being, to form one composite substance, partly corporeal and partly spiritual.

(_c_) This in turn suggests the division of substances into _simple_ and _composite_. The latter are those which we understand to be constituted by the natural and substantial union of two really distinct but incomplete substantial principles, a formative, determining, specifying principle, and a material, determinable, indifferent principle: such are all corporeal substances whether inorganic, vegetative, sentient, or rational. The former, or simple substances, are those which we understand to be constituted by a sole and single substantial principle which determines and specifies their essence, without the conjunction of any material, determinable principle. We have no direct and immediate experience of any _complete_ created substance of this kind; but each of us has such direct experience of an _incomplete_ simple substance, _viz._ his own soul; while we can infer from our experience the _existence_ of other incomplete simple substances, _viz._ the formative principles of corporeal substances, as also the _possibility_ of such complete simple substances as pure spirits, and the actual _existence_ of the perfectly simple, uncreated substance of the Infinite Being.

(_d_) If there are such things as composite substances, _i.e._ substances constituted by the substantial union of two really distinct principles, then it follows that while the composite substance itself is _complete_, each of its substantial constitutive principles is _incomplete_. Of course there are many philosophers nowadays who reject as mere mental fictions, as products of mere logical distinctions, and as devoid of objective validity, the notions of _composite_ substance and _incomplete_ substance. Nor is this to be wondered at when we remember what a variety of groundless and gratuitous notions are current in regard to substance itself (64). But understanding substance in the traditional sense already explained (62), there is nothing whatever inconsistent in the notion of a composite substance, or of an incomplete substance,—provided these notions are understood in the sense to be explained presently. Nay, more, not only are these notions intrinsically possible: we must even hold them to be objectively valid and real, to be truly expressive of the nature of reality, unless we are prepared to hold that there is no such thing as substantial change in the universe, and that man himself is a mere _aggregate_ of material atoms moved according to mechanical laws and inhabited by a conscious soul, or thinking principle, rather than an individual being with one definite substantial nature.

What, then, are we to understand by complete and incomplete substances respectively? A substance is regarded as complete in the fullest sense when it is wanting in no _substantial_ principle without which it would be incapable of _existing_ and discharging _all_ its functions in the actual order as an individual of some definite species. Of course no created substance exists or discharges its functions unless it is endowed with some accidents, _e.g._ with properties, faculties, forces, etc. But there is no question of these here. We are considering only the essential perfections of the substance. Thus, then, any existing individual of any species—a man, a horse, an oak—is a complete substance in this fullest sense. It is complete _in the line of substance_, in _substantial_ perfection, “_in ordine substantialitatis_,” inasmuch as it can exist (and does actually exist) without being conjoined or united substantially with any other substance to form a composite substance other than itself. And it is complete _in the line of specific perfection_, “_in ordine speciei_,” because not only can it exist without such conjunction with any other substantial principle, but it can discharge _all_ the functions natural to its species, and thus tend towards its _final_ perfection (47) without such conjunction.

But it is conceivable that a substance might be complete in the line of substantial perfections, and thus be capable of _existing_ in the actual order and discharging there _some_ of the functions of its species without conjunction with any other substantial principle, and yet be incapable of discharging _all_ the functions natural to an individual of its species without conjunction with some other substantial principle, in which case it would be _incomplete_ in the line of _specific_ perfection, though complete in everything pertaining to its _substantiality_. We know of one such substance,—the human soul. Being spiritual and immortal, it can exist apart from the body to which it is united by nature, and in this separated condition retain and exercise its spiritual faculties of intellect and will; it is therefore complete as regards the distinctively substantial perfection whereby it is “capable of existing in itself”. But being of its nature destined for union with a material principle, constituting an individual of the human species only by means of such union, and being capable of discharging some of the functions of this species, _viz._ the sentient and vegetative functions, only when so united, it has not _all_ the perfections of its species independently of the body; and it is therefore an incomplete substance in the line of specific perfections, though complete in those essential to its substantiality.

Again, if it be true that just as man is composed of two substantial principles, soul and body, so every living thing is composed of a substantial vital principle and a substantial material principle, and that every inorganic individual thing is likewise composed of two really distinct substantial principles, a formative and a passive or material principle; and if, furthermore, it be true that apart from the spiritual principle in man every other vital or formative principle of the composite “things” of our experience is of such a nature that it cannot actually exist except in union with some material principle, and _vice versa_,—then it follows necessarily that all such substantial principles of these complete composite substances are themselves _incomplete_ substances: and incomplete not only in regard to perfections which would make them subsisting individuals of a species, but (unlike the human soul) incomplete even in the line of substantiality itself, inasmuch as no one of them is capable of actually existing at all except in union with its connatural and correlative principle.

Thus we arrive at the notion of substances that are _incomplete_ in the line of specific perfections, or in that of substantial perfections, or even in both lines. An incomplete substance, therefore, is not one which verifies the definition of substance only in part. The incomplete substance _fully_ verifies the definition of a substance.(280) It is conjoined, no doubt, _with another_ to form a complete substance; but it does not exist _in the other_, or in the composite substance, as accidents do. It is _a substantial_ principle of the composite substance, not an _accidental_ determination of the latter, or of the other substantial principle with which it is conjoined. It thus verifies the notion of substance as a mode of being which naturally exists in itself; and united with its correlative substantial principle it discharges the function of supporting all accidental determinations which affect the composite substantial essence. Since, however, it does not exist itself independently as an individual of a species, but only forms the complete individual substance by union with its correlative substantial principle, it may be, and has been, accurately described as not belonging to the category of substance _formally_, but only _referentially_, “_reductivé_”.

The concepts of composite substance, of complete and incomplete substances, understood as we have just explained them, are therefore perfectly intelligible in themselves. And this is all we are concerned to show in the present context. This is not the place to establish the theses of psychology and cosmology from which they are borrowed. That the human soul is spiritual and immortal; that its union with a really distinct material principle to form the individual human substance or nature is a substantial union; that all living organisms and all inorganic bodies are really composite substances and subject to substantial change: these various theses of scholastic philosophy we here assume to be true. And if they are true the conception of incomplete substances naturally united to form a complete composite substance is not only intelligible as an hypothesis but is objectively true and valid as a thesis; and thus the notion of an incomplete substance is not only a consistent and legitimate notion, but is also a notion which gives mental expression to an objective reality.

We may add this consideration: The concept of an accident really distinct from its substance involves no intrinsic repugnance. Yet an accident is a mode of being which is so weak and wanting in reality, if we may speak in such terms, that it cannot naturally exist except by inhering, mediately or immediately, in the stronger and more real mode of being which is substance. But an incomplete substance is a higher grade of reality than any accident. Therefore if accidents can be real, _a fortiori_ incomplete substances can be real.

71. SUBSTANCE AND NATURE.—We have already pointed out (13) that the terms “essence,” “substance,” and “nature” denote what is really the same thing, regarded under different aspects. The term “essence” is somewhat wider than “substance,” inasmuch as it means “what a thing is,” whether the thing be a substance, an accident, or a concrete existing individual including substance and accidents.

The traditional meaning of the term “nature” in Aristotelian and scholastic philosophy is unmistakable. It means the essence or substance of an individual person or thing, regarded as _the fundamental principle of the latter’s activities_. Every finite individual comes into existence incomplete, having no doubt its _essential_ perfections and properties _actually_, but its _intermediate_ and _final_ perfections only _potentially_ (47). These it realizes gradually, through the exercise of its connatural activities. Every being is essentially intended for activity of some sort: “Omne ens est propter suam operationem,” says St. Thomas. And by the constant interplay of their activities these beings realize and sustain the universal order which makes the world a _cosmos_. There is in all things an immanent purpose or finality which enables us to speak of the whole system which they form as “Universal _Nature_”.(281)

Therefore what we call a _substance_ or _essence_ from the _static_ point of view we call a _nature_ when we consider it from the _dynamic_ standpoint, or as an agent.(282) No doubt the forces, faculties and powers, the active and passive accidental principles, whereby such an agent exerts and undergoes action, are the _proximate_ principles of all this action and change, but the _remote_ and fundamental principle of the latter is the essence or substance of the agent itself, in other words its _nature_.

Not all modern scholastics, however, are willing thus to identify
nature with substance. We have no intuitive insight into what any
real essence or substance is; our knowledge of it is discursive,
derived by inference from the phenomena, the operations, the
conduct of things, in accordance with the principle, _Operari
sequitur esse_. Moreover, the actually existing, concrete
individual—a man, for instance—has a great variety of activities,
spiritual, sentient, vegetative, and inorganic; he has, moreover,
in the constitution of his body a variety of distinct organs and
members; he assimilates into his body a variety of inorganic
substances; the tissues of his body _appear_ to be different _in
kind_; the vital functions which subserve nutrition, growth and
reproduction are at least analogous to mechanical, physical and
chemical changes, if indeed they are not really and simply such;
it may be, therefore, that the _ultimate material_ constituents of
his body remain _substantially unaltered_ in their passage into,
and through, and out of the cycle of his vegetative life; that
they retain their elemental _substantial forms_ while they assume
a _new nature_ by becoming parts of the one organic whole, whose
higher directive principle dominates and co-ordinates all their
various energies.(283) If this be so there is in the same
individual a multiplicity of really and actually distinct
substances; each of these, moreover, has its own existence
proportionate to its essence, since the existence of a created
reality is not really distinct from its essence; nor is there any
reason for saying that any of these substances is incomplete; what
we have a right to say is that no one of them separately is a
complete _nature_, that each being an _incomplete nature_ unites
with all the others to form one _complete nature_: inasmuch as no
one of them separately is an adequate intrinsic principle of all
the functions which it can discharge, and is naturally destined to
discharge, by its natural union with the others, whereas there
results from their union a _new fundamental principle_ of a
co-ordinated and harmonized system of operations—in a word, a _new
nature_.

This line of thought implies among other things (_a_) the view
that whereas there is no ground for admitting the existence of
_incomplete substances_, there is ground for distinguishing
between _complete and incomplete natures_; (_b_) the view that
from the union or conjunction of an actual multiplicity of
substances, each remaining unaltered and persisting in its
existence actually distinct from the others, there _can_ arise one
single complete nature—a nature which will be _one being_ simply
and really, _unum ens per se et simpliciter_, and not merely an
aggregate of beings or an accidental unity, _unum per
accidens_,—and there _does_ arise such a nature whenever the
component substances not merely co-operate to discharge certain
functions which none of them could discharge separately (which
indeed is true of an accidental union, as of two horses drawing a
load which neither could draw by itself), but when they unite in a
more permanent and intimate way according to what we call “natural
laws” or “laws of nature,” so as to form a new fundamental
principle of such functions.(284) These views undoubtedly owe
their origin to the belief that certain facts brought to light by
the physical and biological sciences in modern times afford strong
evidence that the elementary material constituents of bodies,
whether inorganic or living, remain _substantially unaltered_
while combining to form the multitudinous _natural kinds_ or
_natures_ of those living or non-living material things. It was to
reconcile this supposed _plurality_ of _actually distinct_ and
_diverse_ substances in the individual with the indubitable _real
unity_ of the latter, that these philosophers distinguished
between substance and nature. But it is not clear that the facts
alleged afford any such evidence. Of course if the philosopher
approaches the consideration of it with what we may call the
atomic preconception of material substances as permanent,
unchangeable entities, this view will preclude all recognition of
_substantial_ change in the universe; it will therefore force him
to conclude that each individual, composite agent has a unity
which must be _less_ than substantial, and which, because he feels
it to be _more_ than a mere accidental or artificial unity, he
will describe as _natural_, as a union to form _one nature_. But
if he approach the evidence in question with the view that
substantial change is possible, this view, involving the
recognition of incomplete substances as real, will remove all
necessity for distinguishing between substance and nature, and
will enable him to conclude that however various and manifold be
the activities of the individual, their co-ordination and
unification, as proceeding from the individual, point to a
_substantial_ unity in the latter as their fundamental principle,
a unity resulting from the _union of incomplete substances_.

This latter is undoubtedly the view of St. Thomas, of practically
all the medieval scholastics, and of most scholastics in modern
times. Nor do we see any sufficient reason for receding from it,
or admitting the modern distinction between substance and nature.
And if it be objected that the view which admits the reality of
incomplete substances and substantial change is as much a
preconception as what we have called the atomic view of substance,
our answer is, once more, that since we have no intellectual
intuition into the real constitution of the substances which
constitute the universe, since we can argue to this only by
observing and reasoning from their activities on the principle
_Operari requitur esse_, the evidence alone must decide which view
of these substances is the correct one. Does the evidence afforded
us by a scientific analysis of all the functions, inorganic,
vegetative, sentient and rational, of an individual man, forbid us
to conclude that he is one complete substance, resulting from the
union of two incomplete substantial principles, a spiritual soul
and a material principle? and at the same time compel us to infer
that he is one complete nature resulting from the union of a
plurality of principles supposed to be complete as substances and
incomplete as natures? We believe that it does not; nor can we see
that any really useful purpose is served by thus setting up a real
distinction between substance and nature. From the evidence to
hand it is neither more nor less difficult to infer unity of
substance than unity of nature in the individual. The inference in
question is an inference from facts in the phenomenal order, in
the domain of the senses, to what must be actually there in the
noumenal order, in the domain of nature or substance, a domain
which cannot be reached by the senses but only by intellect. Nor
will any imagination images which picture for us the physical
fusion or coalescence of material things in the domain of the
senses help us in the least to conceive in any positive way the
mode in which incomplete natures or substances unite to form a
complete nature or substance. For these latter facts belong to the
domain which the senses cannot reach at all, and which intellect
can reach only inferentially and not by direct insight.

Hence we consider the view which regards real unity of nature as
compatible with real and actual plurality of complete substances
in the individual, as improbable. At the same time we do not
believe that this view is a necessary corollary from the real
identification of essence with existence in created things. We
have seen that even if accidents have their own existence in so
far as they have their own essence—as they have if essence and
existence be really identical—nevertheless the concrete substance
as determined by its accidents can have a really unitary
existence, _unum esse_ corresponding to and identical with its
composite constitution (67). Similarly, if the existence of each
incomplete substance is identical with its incomplete essence,
this is no obstacle to the complete substance—which results from
the union of two such incomplete substantial principles—having one
complete unitary existence identical with its composite essence.
Hence it is useless to argue against the view that a plurality of
actually distinct and complete substances can unite to form a
complete nature which will be really _one being_, on the ground
that each complete substance has already its own existence and
that things which have and preserve their own existence cannot
form _one being_. Such an argument is inconclusive; for although
_one being_ has of course only one existence, it has not been
proved that this one existence cannot result from the union of
many incomplete existences: especially if these existences be
identical with the incomplete essences which are admittedly
capable of uniting to form one complete essence.

It may, however, be reasonably urged against the opinion under
criticism that, since the complete substances are supposed to
remain complete and unchanged in their state of combination, it is
difficult to see how this combination can be a real union and not
merely an extrinsic juxtaposition,—one which remains in reality a
merely accidental conjunction, even though we may dignify it with
the title of a “natural union”.

And finally it may be pointed out that in this view the operations
of the individual have not really _one ultimate_ intrinsic
principle at all, since behind the supposed unity of nature there
is a more fundamental plurality of actually distinct substances.

72. SUBSISTENCE AND PERSONALITY.—We have already examined the relation between the individual and the universal, between _first_ and _second_ substances, in connexion with the doctrine of Individuation (31-3). And we then saw that whatever it be that individuates the universal nature, it is at all events not to be regarded as anything extrinsic and superadded to this nature in the individual, as anything really distinct from this nature: that, for instance, what makes Plato’s human nature to be Plato’s is not anything really distinct from the human nature that is in Plato. We have now to fix our attention on the nature as individualized. We have to consider the complete individual nature or substance itself in actually existing individual “things” or “persons”.

We must remember that scholastics are not agreed as to whether there is a real distinction or only a virtual distinction between the actual existence and the complete individual essence or substance or nature of created individual beings (21-4). Furthermore we have seen that philosophers who study the metaphysics of the inorganic world and of the lower forms of life are unable to say with certainty what is the individual in these domains: whether it is the chemical molecule or the chemical atom or the electron; whether it is the single living cell or the living mass consisting of a plurality of such cells (31). But we have also seen that as we ascend the scale of living things all difficulty in designating the genuine individual disappears: that a man, a horse, an oak tree, are undoubtedly individual beings.

Bearing these things in mind we have now to inquire into what has been called the _subsistence_ or _personality_ of the complete individual substance or nature: that perfection which enables us formally to designate the latter a “subsisting thing”(285) or a “person”. By personality we mean the subsistence of a complete individual _rational_ nature. We shall therefore inquire into the meaning of the generic term _subsistentia_ (or _suppositalitas_), _subsistence_, in the abstract. But let us look at it first in the concrete.

A complete individual nature or substance, when it exists in the actual order, really distinct and separate in its own complete entity from every other existing being, exercising its powers and discharging its functions of its own right and according to the laws of its own being, is said to _subsist_, or to have the perfection of _subsistence_. In this state it not only _exists in itself_ as every substance does; it is not only _incommunicable_ to any other being as every individual is, in contradistinction with _second_ or _universal_ substances which are, as such, indefinitely communicable to individuals; but it is also a complete whole, incommunicable _as a mere integral or essential part_ to some other whole, unlike the incomplete substantial constituents, or integral parts, members or organs of, say, an individual organic body; and finally it is incommunicable in the sense that it is not capable of being assumed into the subsisting unity of some other superior “suppositum” or “person”. All those characteristics we find in the individual “subsisting thing” or “person”. It “exists in itself” and is not communicable to another substance _as an accident_, because it is itself a substance. It is not communicable _to individuals as a universal_, because it is itself an individual. It is not communicable _as an integral or essential part to a whole_, because it is itself a complete substance and nature.(286) Finally it is not communicable to, and cannot be assumed into, the unity of a higher personality so as to subsist by virtue of the latter’s subsistence, because it has a perfection incompatible with such assumption, _viz._ its own proper subsistence, whereby it is already an actually subsisting thing or person in its own right, or _sui juris_, so to speak.

The mention of this last sort of incommunicability would be
superfluous, and indeed unintelligible, did we not know from
Divine Revelation that the human nature of our Divine Lord and
Saviour, Jesus Christ, though it is a complete and most perfect
individual nature, is nevertheless _not a person_, because It is
assumed into the Personality of the Second Person of the Divine
Trinity, and, united hypostatically or personally with this Divine
Person, subsists by virtue of the Divine Subsistence of the
latter.

We see, therefore, what subsistence does for a complete individual nature in the _static_ order. It makes this nature _sui juris_, incommunicable, and entirely independent in the mode of its actual being: leaving untouched, of course, the essential dependence of the created “subsisting thing” or “person” on the Creator. In the _dynamic_ order, the order of activity and development, subsistence makes the complete individual nature not only the ultimate principle _by which_ all the functions of the individual are discharged, but also the ultimate principle or agent _which_ exercises these functions: while the nature _as such_ is the ultimate _principium_ QUO, the nature _as subsisting_ is the ultimate _principium_ QUOD, in regard to all actions emanating from this nature. Hence the scholastic aphorism: _Actiones sunt suppositorum_. That is, all actions emanating from a complete individual nature are always ascribed and attributed to the latter _as subsisting_, to the “subsisting thing” or “person”. In regard to an individual human person, for instance, whether his intellect thinks, or his will resolves, or his imagination pictures things, or his eyes see, or his hand writes, or his stomach digests, or his lungs breathe, or his head aches, it is the _man_, the _person_, properly, that discharges or suffers all these functions, though by means of different faculties, organs and members; and it is to him properly that we ascribe all of them.(287)

Now the individual human person is neither his soul, nor his body, nor even both conceived as two; he is _one_ being, one complete substance or nature composed partly of a spiritual principle or soul and partly of a material principle which the soul “informs” and so constitutes a living human body. Hence the human soul itself, whether we consider it as united to the material principle in the living human person, or as disembodied and separate from its connatural material principle, is not a complete substance, is not capable of _subsisting_ and having its human activities referred ultimately to itself as the subsisting, personal principle which elicits these activities. No doubt the disembodied soul has actual _existence_, but it has not the perfection of _subsistence_ or _personality_: it is not a complete individual of the human species to which it belongs, and therefore it cannot be properly called a human person, a complete subsisting individual of the human species.(288)

Furthermore, even though an individual nature be complete as a
nature, endowed with all the substantial and specific perfections
which constitute it a complete individual of the species to which
it belongs, nevertheless if it is assumed into the personality of
another and higher nature, and subsists in personal union with the
latter and by virtue of the latter’s subsistence, then that
nature, not having its own proper and connatural subsistence, is
not itself a person. Nor can the actions which are elicited by
means of it be ascribed ultimately to it; they must be ascribed to
the person by whose subsistence it subsists and into whose
personality it has been assumed. If an individual human nature be
thus hypostatically or personally assumed into, and united with, a
higher Divine Personality, and subsists only by this Personality,
such a human nature will be really and truly an individual nature
of the human species; the actions elicited through it and
performed by means of it will be really and truly human actions;
but it will not be a human person; while its actions will be
really and truly the actions of the Divine Person, and will
therefore be also really and truly divine: they will be the
actions of the God-Man, divine and human, _theandric_. All this we
know only from Divine Revelation concerning the hypostatic union
of the human nature of Christ with the Person of the Divine Word;
nor could we know it otherwise. But all this does not modify, it
only supplements and completes, what the light of reason discloses
to us regarding the subsistence or personality of any complete
individual nature.

We are now in a position to give nominal definitions of subsistence and personality both in the abstract and in the concrete, _i.e._ definitions which will indicate to us what exactly it is that these terms denote,(289) and which will thus enable us to inquire into their connotation, or in other words to ask what is it precisely that constitutes subsistence or personality.

By “_subsistence_” (“_subsistentia_,” “_suppositalitas_”) we mean that perfection whereby a fully complete individual nature is rendered in every way, in its being and in its actions, distinct from and incommunicable to any and every other being, so that it exists and acts _sui juris_, autonomously, independently of every other being save the Creator.(290)

By a “_subsisting being_” in the concrete (ὑπόστασις, “_suppositum_,” _hypostasis_), we mean a being endowed with this perfection of subsistence; in other words, a being that is a complete individual nature existing and acting in every way distinct from and incommunicable to any other being, so that it exists and acts _sui juris_, autonomously.

“_Personality_” is simply the subsistence of a complete individual nature that is _rational_, _intelligent_.

A “_person_” is simply a _subsisting_ nature that is _rational_, _intelligent_: _Persona est suppositum rationale_. The definition given by Boëtius is classic: “_Persona est substantia individua_ RATIONALIS _naturae_”: “the individual substance of a rational nature,”—where the term _individual_ is understood to imply _actually existing and subsisting_.

The special name which has thus been traditionally applied to _rational_ or _intelligent_ subsisting beings (as distinct from animals, plants, and material “things”)—the term “person” (“_persona_,” a mask: _per-sonus_; _cf._ Gr. προσωπέιον, from προσώπον, the face, countenance)—originally meaning a rôle or character in a drama, came to be applied to the subsisting human individual, and to connote a certain dignity of the latter as compared with the lower or non-rational beings of the universe. And in fact the ascription of its actions to the subsisting being is more deeply grounded in the subsistence of rational, intelligent beings, who, as free agents, can more properly direct and control these actions.(291)

73. DISTINCTION BETWEEN THE INDIVIDUAL NATURE AND ITS SUBSISTENCE. WHAT CONSTITUTES PERSONALITY?—Knowing now what we mean by the terms “subsistence,” “suppositum,” “person,” and “personality,” we have next to inquire in what precisely does subsistence consist. What is it that constitutes a complete individual nature a “subsisting being,” or if the nature be rational, a “person”? Subsistence connotes, over and above the mode of “existing in itself” which characterizes all substance, the notion that the substance or nature is individual, that it is complete, that it is in every way incommunicable, that it is _sui juris_ or autonomous in its existence and activities. These notions are all positive; they imply positive perfections: even incommunicability is really a positive perfection though the term is negative. But is any one of the positive perfections, thus contained in the notion of subsistence, a positive something _over and above_, and _really distinct from_, the perfection already implied in the concept of _a complete individual nature as such_?

Some of those philosophers who regard the distinction between essence and existence in creatures as a real distinction, identify the _subsistence_ of the complete individual nature with its _actual existence_, thus placing a real distinction between nature and subsistence or personality.(292) Apart from these, however, it is not likely that any philosophers, guided by the light of reason alone, would ever have held, or even suspected, that the subsistence of an actually existing individual nature is a positive perfection really distinct from, and superadded to, the latter. For we never, in our natural experience, encounter an existing individual substance, or nature, or agent, that is not distinct, autonomous, independent, _sui juris_, and incommunicable in its mode of being and acting.

Rigorously, however, this would only prove that subsistence is a
perfection _naturally inseparable_ from the complete individual
nature; _conceivably_ it _might_ still be _really_ distinct from
the latter. But whether or not such real distinction could be
suspected by the unaided light of reason working on natural
experience, at all events what we know from Divine Revelation
concerning the hypostatic union of the human nature of our Lord
Jesus Christ with the Person of the Divine Word, enables us to
realize that there _can_ be, in the actual order of things, a
complete individual nature which is not a “subsisting being” or
“person”; for the human nature of our Lord is _de facto_ such a
nature,—and _ab actu ad posse valet consecutio_. This information,
however, is not decisive in determining the character of the
distinction between the individual substance or nature and its
subsistence.

It may be that the complete individual nature is _eo ipso_ and identically a “subsisting being” or “person,” that it is always independent, autonomous, _sui juris_, by the very fact that it is a complete individual nature, _unless it is_ DE FACTO _assumed into the personality of a higher nature_, so that in this intercommunication with the latter, in the unity of the latter’s personality, it is not independent, autonomous, _sui juris_, but dependent, subordinate, and _alterius juris_. In this condition, it loses nothing positive by the fact that it is not now a person and has not its own subsistence; nor does it gain any _natural_ perfection, for it was _ex hypothesi_ complete and perfect _as a nature_; but it gains something _supernatural_ inasmuch as it now subsists in a manner wholly undue to it.(293) According to this view, therefore, subsistence would not be a perfection really distinct from the complete individual nature; it would be a mentally distinct aspect of the latter, a positive aspect, however, consisting in this nature’s completeness, its self-sufficing, autonomous character, and consequent incommunicability.(294)

The principal difficulty against this view is a theological
difficulty. As formulated by Urraburu,(295) it appears to involve
an ambiguity in the expression “substantial union”. It is briefly
this: If the subsistence proper to a complete individual nature
adds no positive perfection to the latter, so that the latter
necessarily subsists and is a person unless it is actually assumed
into a higher personality, and by the very fact that it is not
actually so assumed, then the human nature of Christ “is as
complete in every way and in every line of substantial perfection,
by virtue of its own proper entity, when actually united with the
Divine Person, as it would be were it not so united, or as the
person of Peter, or Paul, or any other human person is”. But this
implies that there are in Christ “two substances complete in every
respect”. Now between two such substances “there cannot be a
substantial union,” a union which would constitute “one being,”
“unum per se ens”. Hence the view in question would appear to be
inadmissible.

But it is not proved that the union of “two substances complete in
every respect” cannot result in the constitution of a being that
is really and genuinely one—“unum per se ens”—_in the case in
which the union is a personal union_. The hypostatic union of the
human nature of Christ with the Divine Person is primarily a
_personal_ union whereby the former nature subsists by and in the
Divine Personality. It has the effect of constituting the united
terms “one subsisting being,” and therefore has supereminently, if
not formally, the effect of a “substantial union”. Nay, it is a
“substantial” union in the sense that it is a union of two
substances, not of a substance and accidents; and also in the
sense that it is not a mere accidental aggregation or artificial
juxtaposition of substances, resulting merely in the constitution
of collective or artificial unity, a _unum per accidens_. But is
it a “substantial” union in the sense that it is such a union of
substances as results in one “nature”? Most certainly not; for
this was the heresy of the Monophysites: that in Christ there is
only one nature resulting from the union of the human nature with
the Divine. If then, with Urraburu, we mean by “nature” simply
“substance regarded as a principle of action” (71), and if,
furthermore, the hypostatic union does not result in one “nature,”
neither does it result in one “substance,” nor can it be a
“substantial” or “natural” union in this sense.(296) He does not
say, of course, that the hypostatic union is a “substantial union”
which results in “one nature,” or even explicitly that it results
in “one substance,” but he says that the two substances are
“substantially conjoined,” “substantialiter conjunguntur”; and he
continues, “a substantial union is such a conjunction of two
substantial realities that there results from it one substantial
something, which is truly and properly one”—“unio enim
substantialis, est talis duarum rerum substantialium conjunctio,
per quam resultat unum aliquid substantiale quod vere et proprie
sit unum,”(297)—and he concludes that “there is something
substantial wanting in the human nature of Christ, _viz._
personality, which, of course, is most abundantly supplied in the
hypostatic union by the Divine Person”—“reliquum est, ut naturae
humanae in Christo aliquid desit substantiale, nempe personalitas,
quod per unionem hypostaticam cumulatissime suppleatur a
Verbo.”(298) Now, this “aliquid substantiale” cannot be “aliquid
naturale” in the sense that it is something _constitutive_ of the
human substance or nature; for the human substance or nature of
Christ is certainly complete and perfect as a substance or nature.
It must be some complement or mode, that is naturally due to it,
but supernaturally supplied by the Person of the Divine Word.(299)
This brings us to the view that subsistence is a something
positive, distinct in some real way, and not merely in our
concepts, from the complete individual substance.

According to the more common view of catholic philosophers (and theologians) subsistence is some positive perfection really distinct from the complete individual nature. But the supporters of this general view explain it in different ways. We have already referred to the view of certain Thomists who, identifying _subsistence_ with the _actual existence_ of the complete substance or nature, place a real distinction between the existence and the substance or nature. Other Thomists, while defending the latter distinction, point out that actual existence confers no real perfection, but only actualizes the real; they hold, therefore, that subsistence is not existence, but is rather a perfection of the real, essential, or substantial order, as distinct from the existential order—a perfection presupposed by actual existence, and whose proper function is to _unify_ all the substantial constituents and accidental determinations of the individual substance or nature, thus making it a really unitary being—“unum ens per se”—proximately capable of being actualized by the simple existential act: which latter is the ultimate actuality of the real being: _esse est ultimus actus_.(300)

The concrete individual nature, containing as it does a plurality of really distinct principles, substantial and accidental, needs some unifying principle to make these one incommunicable reality, proximately capable of receiving a corresponding unitary existential act: without such a principle, they say, each of the substantial and accidental principles in the concrete individual nature would have its own existence: so that the result would be not _really_ one being, but a being really _manifold_ and only accidentally one—“unum per accidens”. This principle is _subsistence_.

The human nature of our Divine Lord has not its own connatural
subsistence; this is supplied by the subsistence of the Divine
Person. Moreover, since the human nature in question has not its
own subsistence, neither has it its own existence; existence is
the actuality of the subsisting being; therefore there is in
Christ but one existence, that of the Divine Person, whereby also
the human nature of Christ exists.(301)

Of those who deny that the distinction between the existence and the essence of any created nature is a real distinction, some hold in the present matter the Scotist view that subsistence is not a positive perfection really distinct from the complete individual nature. Others, however, hold what we have ventured to regard as the more common view: that personality is something positive and really distinct from nature. But they explain what they conceive subsistence to be without any reference to existence, and without distinguishing between the essential and the existential order of reality.

The most common explanation seems to be that subsistence is a unifying principle of the concrete individual nature, as stated above. Thus conceived, it is not an _absolute_ reality; nor is the distinction between it and the nature a _major_ real distinction. It is a _substantial mode_ (68), naturally superadded to the substance and modally distinct from the latter. It so completes and determines the substance or nature that the latter not only exists in itself but is also, by virtue of this mode, incommunicable in every way and _sui juris_.(302) It gives to the substance that ultimate determinateness which an accidental mode such as a definite shape or location gives to the accident of quantity.(303)

This mode is absent (supernaturally) from the human nature of our
Divine Lord; this nature is therefore communicable; and the
Personality of the Divine Word supernaturally supplies the
function of this absent natural mode.

It must be confessed that it is not easy to understand how this or any other _substantial_ mode can be _really_ distinct from the substance it modifies. And in truth the distinction is not real in the full sense: it is not between _thing_ and _thing_, _inter rem et rem_. All that is claimed for it is that it is not merely mental; that it is not merely an _ens rationis_ which the mind projects into the reality; that it is a positive perfection of the nature or substance, a perfection which, though naturally inseparable from the latter, is not absolutely inseparable, and which, therefore, is _de facto_ supernaturally absent from the human nature and replaced by the Divine Personality in the case of the hypostatic union.

It belongs, moreover, to the order of substance, not to that of accidents: the substantial mode differs from the accidental mode, or modal accident, in this, that it gives to the substance some ultimate determining perfection which appertains to the substance as such, and whereby the substance is completed in the order of “existing in itself”. Subsistence is not an accident, even though it supervenes on the complete nature, for it determines the substance of the latter, not in relation to any line of accidental activity, as a power or faculty, nor as something modifying it accidentally, but as a mode which ultimately determines and perfects it in the order of substantial reality itself, in the order of “existing in itself” in such a full and perfect manner as to be _sui juris_ and incommunicable.

The main difficulty against this view is also theological: If
subsistence is a positive perfection it either belongs to the
complete individual nature or it does not; in the former case the
humanity of Christ, assumed by the Divine Word, was not a complete
human nature; in the latter case the individual human nature can
exist without it: and both consequences are equally inadmissable.
But it may be replied that, granting the first member of the
disjunctive, the consequence inferred from it does not really
follow: subsistence belongs to the complete individual nature as
an ultimate natural complement; but when it is absent and supplied
supernaturally by the Divine Personality the nature is still
complete as a nature: it is wanting in no absolute or entitative
perfection, but only in a modality which is supereminently
supplied by the Divine Personality. Neither is the consequence
from the second member of the disjunctive a valid inference. For
though personality as a mode does not belong to the essence of an
individual human nature, no such individual nature can exist
without _some_ personality, either its own or another: just as
extension cannot exist without _some_ shape, though any particular
shape is not essential to it.

To sum up, then, the doctrine of the two preceding sections: What are we to understand by a _person_, and by _personality_? Unquestionably our conception of person and personality (concrete and abstract) is mainly determined, and very rightly so, by an analysis of what constitutes the actually existing individual of the human species. Whatever our concept be, it must certainly be realized and verified in all human individuals: these, before all other beings, must be included in the denotation of our concept of person. In fact, for the philosopher, guided by the natural light of reason alone, the term can have hardly any other connotation. He will, no doubt, ascribe personality, as the highest mode of being he knows of, to the Supreme Being; but he will here ascribe it only in an analogical and supereminent way; and only from Divine Revelation can he know that this Supreme Being has not a single but a threefold Personality. Again, his consideration of the nature of the human soul as an embodied substance which is nevertheless spiritual and immortal will enable him to affirm the possibility of _purely spiritual_ created beings; and these he will of course conceive as persons. But, conceiving the human soul itself as a constituent principle of the human individual, he will not conceive the soul itself as a person.

The philosopher who understands the traditional Aristotelian conceptions of substance, of individual substance (_substantia prima_), of incomplete, complete, and composite substances, of substance considered as _nature_ or principle of action, of substance considered as _hypostasis_, as the actually existing individual being which is the ultimate logical subject of all predications and the ultimate ontological subject of all real determinations: the philosopher who understands these concepts, and who admits them to be validly grounded in experience, and to offer as far as they go a correct interpretation of reality, will have no difficulty in making up his mind about what is requisite to constitute a person.

Wherever he finds an existing individual being of any species, a being which, even if it is really composite, is nevertheless really one, such a being he will pronounce to be a “subsisting individual being”. He may not be able, in the inorganic world or among the lower forms of life, to distinguish for certain what is the real individual from what may be perhaps only an accidental, if natural, colony or group of real individuals. As a test he will always seek for the manifestation of an internal directive principle whereby all the vital functions of the organized mass of matter in question are co-ordinated in such a manner as to make for the preservation, growth and development of the whole throughout a definite life cycle from birth to death. This formative and directive principle is evidence of an individual unity of nature and subsistence; and such evidence is abundantly present in “individuals” of all the higher species in botany and zoology. The “individual subsisting being” will therefore be a “complete individual substance or nature, existing and acting in every way distinct from and incommunicable to any other being, so that it exists and acts _sui juris_, autonomously”.

If such an individual nature is not merely corporeal but organic or animate, not merely animate but sentient, and not merely sentient but _rational_ or _intelligent_, _i.e._ constituted at least in part by a _spiritual substantial principle_ whereby the individual is _intelligent_ and _free_, then that individual is a person. Every individual of the human species is such. And all that is essential to his complete individual human nature enters into and constitutes his person in the concrete. Not merely, therefore, his intellect and will; not merely his soul considered as “mind,” _i.e._ as the basis and principle of his whole conscious and subconscious psychic life; or also as the principle of his merely organic life; or also as the actualizing principle of his corporeal nature; but no less also the corporeal principle itself of his composite being, the body itself with all its parts and members and organs: all these without exception belong equally to the human person; all of them without exception go to constitute the _Ego_.(304) This, which is the Aristotelian and scholastic view of the human person, is in perfect accord with the common-sense view of the matter as evidenced by the ordinary usages of language. We speak intelligibly no less than correctly when we say that a man’s body is part of his person as well as his soul or mind. And we make a no less accurate, intelligible, and necessary distinction, when we distinguish between all that which _constitutes_ the human person and that _whereby we know_ ourselves and other human individuals to be persons. Yet this distinction is not kept clearly in mind by many modern philosophers, who, approaching the study of personality exclusively from the side of what the individual consciousness testifies as to the unity and continuity (or otherwise) of mental life in the individual, are scandalized at the assertion that the human body can have anything to do with human personality.