Phil. 102Metaphysics

A Few Notes on Aquinas’ On Being and Essences

p. 27    Prologue

“The Philosopher” = Aristotle

Avicenna =Ibn Sina (980-1037).  One of the most important of the Medieval Islamic  philosophical thinkers.  Some of his most important writings were translated  into Latin from Arabic in Spain in the 12th century.  His philosophy is one of  existence (wujud).

Chapter 1

(1) We begin with the meaning of “being” because it is easier to grasp at first, then we will consider the meaning of “essence.”

(2) “A being” can denote (1) what is divided by the 10 categories, or (2) it can signify truth for  propositions.  We’ve seen this in Aristotle.  

*  Regarding (2) note that what we mean is that something can be called “a being” if we can  form a positive statement (affirmative proposition) about it.  E.g. Blindness is in the eye.  But, of course, blindness is a negation, not a positively existing thing or being.  Recall Parmenides and Plato who say that we cannot know what is not.

(3) Consequently, “essence” (essential) is derived from “a being” (ens) in the sense (1) above, namely in the sense of the 10 categories.

*  The Great Commentator on Aristotle, Averroes or Ibn Rushd (1126-1198), saw just this and agreed that essence is signified by sense (1) above.

(4) Some philosophers have used the term “quiddity” (literally: whatness) in place of essence because a definition saying what a thing is does so by locating that thing in its genus and species.  E.g., What is man?  Man is an animal of the rational sort.

Aristotle often calls this the “what something was to be” and Avicenna (see note to Prologue) says it’s the form since the form determines what each thing is.  Boethius (of Rome, 480-524) called this the “nature” of a thing.

So we can say that a nature is what the intellect can grasp in any way because the intellectual grasp or full understanding of a thing comes about only through the knowing of its definition and essence.  Generally, then, we might say “nature” indicates the essence as carrying from what the definition and essence.  Generally, then, we might say “nature” indicates the essence as carrying out its specific operation or actuality.  “Quiddity” comes from what the definition signifies.  And “essence” is what is the cause of being in a thing.

(5) Of course, “essence” like “a being” is used primarily and most truly of substances, not accidents, because accidents are qualified beings, that is to say, they are dependent for their being on a substance that they are present it.

(6) Finally, we note that there are composite substances like us and Fido and the flower, and there are simple substances like God and the angels.  But, of course, both kinds have essence since both are substances.

Simple substances are the cause of the others, as God is the cause of composite substances such as us, but we’ll get into that in more detail later.

But given our abilities which are directed toward composite beings of the world of the senses, we must begin learning with what is easier and more at hand for us and slowly progress from composite substances to the understanding of the more difficult which are simple substances.

Chapter Two 

(1) While both form and matter are found in composite substances such as ourselves (as soul and body), it is incorrect to think that either alone is what we mean by essence.

The essence is what is the cause of being of a thing somehow and it is what fixes a thing in a certain species and genus and makes the thing knowable.  But matter is not the cause of actuality in a thing and does not make a thing knowable or to be in a certain species and genus.

What about form alone?  Is it essence?  Well, it does cause actuality in a thing in a way.  But by essence we mean what is signified through the definition.  And definitions of natural things like dogs and trees and men include matter in addition to form.  An animal is soul and body.  And matter is not something additional as is an accident.  Matter is part of what it is to be a man or human because humans are composites of matter and form in their definitions.  Matter is not accidental to being a man; it is essential!  Thus, essence includes both matter and form.

(2) Moreover, essence is not an additional relation between matter and form becuase relations are accidents.  We are after the essential nature.  Form actualizes matter and then the two together in real composition become one being.  (But, of course, since matter is potentiality, it receives actual existence or being from the actualizing form.)

Whatever comes to or accrues to the thing after the composition of matter and form which make the composite exist as an actually existing composite, whatever it is it must be accidental (=an accident), not part of the very essence of the thing. 

And accidental coming-into-being is “qualified coming-into-being” or coming-into-being-in-a-certain-respect, – not absolute coming-into-being.

(3) Thus, essence must be the composite of matter and form.  Boethius agreed to this when he said OUSIA (= substance in our translation of Aristotle) signifies a composite thing.  Avicenna said “quiddity” (See Ch. 1, (3) above) agrees too.  This is quite reasonable because composite substances really do have composite being or existence.  And the essence is the essence of the thing, not of a part.  (Remember: a thing is called an essence because it is first called a being. (See Ch. 1, (3)) The essence of a composite includes both form and matter.  (Yes, I know I said form is in a way the real actual cause of being, of this being, but hold off a little on that question.  I’ll return to it a little later.)

(4) Now, since matter seems to be the principle of individuation in a thing, it might seem that essence only concerns particulars and is not some sort of universal that is knowable.  And if essence is what is signified by the definition, then universals couldn’t have definitions or be defined – if essence only concerns particulars!

But wait a minute.  The matter that individuates is not just any matter, but this designated matter which is under determined dimensions.  We do something else when we consider definitions.  We use the notion of undesignated matter or undetermined matter to fill in where we would otherwise indicate the matter of some determined thing.

So, in the definition of the universal man, we say that man has in its definition bones and flesh because they are essential parts of the definition of man.  But we don’s mean John’s or Lisa’s bones and flesh are in the definition.  We mean bones and flesh considered indeterminately.

(5) So the essence of Socrates is the essence of this man whose form and matter are determinately designated and which make up that composite being whose name is Socrates.

These same notions of designated and undesignated also apply to the notions of the essence of the genus and the essence of the species.

Matter designates the individual with respect to species and species is designated by the difference with respect to genus.  (Regarding the latter we mean that man is designated by his rationality with respect to the genus animal which contains many other sorts of animals as well.)

(6) Let’s consider this further for clarity because we want to have a clear understanding of how the genus implicitly contains the species in an indeterminate way, yet can be understood alone as “prescinding from any other perfection.”

“Body” is equivocal, that is, it can have several meanings.  Body can mean a part of an animal and it can also mean a genus which is quite different from an integral part of a thing.

(A) The term “body” can be used to designate a thing which possesses form determines it to have three dimensions in it, prescinding from (= absolutely excluding consideration of) anything else which might further determine or perfect it.  Considered in this way, body is to which soul is joined to make up a living being composed of body and soul as two parts.

(7) (B) But body can also be taken as a genus in the sense of any thing having three dimensions regardless what form it may have.  Here body is not a part.  We can say that body here is a genus for animal, body is the genus under which animal is placed.  In this sense animal contains nothing that is not already implicitly contained in the notion of body.

Now the relation of man to animal is similar.  The notion or genus animal implicitly or one might say indeterminately contains man as one of its possible determinations.  Man is one determination of the genus animal.

(8) So the genus signifies indeterminately everything in the species.  And the difference also designates the whole thing, not the form alone.  (Rationality belongs to man as a whole being who is a unity.)  And, as we’ve seen, the definition signifies the whole too.  The genus signifies what awaits the determination of the specific form.

(9) Genus is like matter but not matter.  (Potency)

Difference is like form but not form.  (Determination, actuality)

Man the rational animal is not 2 parts, rational and animal as a composite.

Those are abstract notions, not realities as parts.

Man is body and soul as parts of which man is composed.  Of course, man is neither alone nor 50% and 50% because man is the result of the composition, of the composing, a result which doesn’t exist before the actual composing.  He is a third thing identical with neither of its parts.  (Water is a third thing, neither identical with oxygen nor hydrogen.)

(10) Essence is not genus alone, otherwise we would have the same essence as a dog.  Essence requires that the difference or indetermination of the genus be delimited by the difference to make the species of which there is essence.

(11) As the genus indifferently, indeterminately signifies all the many species (e.g. animal indeterminately signifies man, dog, bird, etc.), so too the species indeterminately signifies all the individuals (e.g. man indeterminately signifies John, Lisa, Cathy, Bill, etc.)

Now humanity designates what makes man to be man.  But it prescinds from (excludes) desginated matter and this designated matter is necessary in real man, John.

(12) Humanity signifies the form of the whole man including both form and matter, but it does so while prescinding from (excluding from consideration) the factors which enable matter to be designated as when we consider this man John whose matter is designated here and now.

(13) The essence of man, then, can be signified in two different ways.

“Man expresses it as a whole, not prescinding from designated matter, but implicitly and indistinctly containing all that is man in individuals having designated matter.  In this way it can be said of (predicated of) individuals such as Marie and Michael.

But “humanity” is not the same, because it prescinds from all designation of matter.  So humanity cannot be predicated of individual men.

For this reason we can say “Socrates is an essence” meaning he is a man; and also we can say, “the essence of Socrates is not Socrates,” meaning humanity is not Socrates.

Chapter Three

(1) What’s the status of essence with respect to genus, species and difference?

Well, genus, species and difference as universal are attributed to an individual determinate thing, so “humanity” or “animality” which signify only a part, not the whole individual determinate thing, do not have the notion of universal.  Avicenna points out that these and also “rationality” are principles of the species, genus and difference, not the very species, genus and difference.

Moreover, we can’t attribute the notions of genus and species to some sort of essence existing as a reality outside the individual things– as Plato seems to have done– because then the notions of genus and species could not be attributed to the individual.  We really can’t say that Paul is a man or a animal but that man or animal exist only separately outside him.  He would be separate from himself.  And, as Aristotle said in Book I of his Metaphysics, if we only knew separate Platonic forms, we couldn’t know things of this world, the individuals in our world of sense experience.  (Recall how Plato criticized the Divided Line in his dialogue Parmenides.)

Therefore, genus and species just don’t apply to essence when essence is expressed as a part (see Ch. 2), essence expressed as a whole, e.g. “Man,” “animal” contains implicitly, indistinctly, indeterminately everything in the individual.

(2) A nature or essence can be considered in two ways.

First, ESSENCE ABSOLUTELY CONSIDERED:

Here we consider the essence only in and of itself, we consider just what belongs to it alone without reference to anything else.  E.g. to man belong “rational” “animal” and any other necessarily definitional characteristics, but man absolutely considered does not have to be white or black to be man.

Now consider the question of whether this essence considered absolutely must be one or many.  If the essence in itself considered absolutely is many (a plurality), it could never be one – but, of course, we know it’s one in Paul.  What if it were just one, in and of itself in the essence?  Paul and Julie could not be individuals, then.  They would have to have one essence.

What shall we say, then?  ESSENCE ABSOLUTELY CONSIDERED IS NEITHER ONE NOR MANY.  (Remember all the Platonic problems over this which we saw raised in Plato’s dialogue Parmenides?)

(3) Secondly, nature or essence can be considered according to the being it has in an individual.

(4) But let’s examine all this more closely.  Nature or essence has a twofold being:

1.  In the individual things, and 

2.  In the soul or mind.

1) In individuals we see nature or essence, existing in a multiple way corresponding to the many different individuals.

No individual has the essence of man absolutely considered.  Rather, each has the essence of man as manifested in one individual existing being.

If the essence of man belonged to Art, then none of us could be human by essence.

But the essence of man must be able to exist in individuals, otherwise no individual could have essence.

So, the essence of man ABSOLUTELY CONSIDERED abstract from every kind of being, “but in such a way that it prescinds from no one of them.”

(5) But in itself ESSENCE ABSOLUTELY CONSIDERED is also not a universal because the essence considered is this way does not have the unity and community (oneness and commonness) included in our proper notion of a universal.

(6) (2) In the soul or mind – or, more precisely, in the intellect – is where essence can be universal.  This is where the notions of species and genus as universal are found.

We abstract from all individuating factors and form in our minds a universal notion which applies to all humans existing outside our minds.  This is a likeness of all that leads to a knowledge of all insofar as they are humans – not insofar as they are individuals.

The notion of species is formed because of the general relation of the mind to things outside, because the mind finds this likeness and attributes it to the nature.  Both Averroes and Avicenna agree that the intellect causes the universality in things.

(7) But, of course, the universality comes from the relation of the form to things as a likeness of those things.  It does not come because of some notion of one universal all encompassing MIND that we all share in (as Averroes thought).

(8) The notion of species then is extrinsic (or accidental) to the essence absolutely considered.  In the mind, the essence can be considered as species, but the essence itself is not necessarily universal.  We don’t have to say Lisa is a species.  That would happen if the notion of species were part of the very notion of essence, even when that essence is absolutely considered.  We want to say that Lisa possesses everything which belongs to a human as a human.  But the notion of essence absolutely considered saves us from this problem.

(9) How, then, is essence related to species?

Species and universality generally belong to the essence as it is considered by the intellect, that is to say, “because of the being it has in the intellect.”  Because of this, the notions of genus and difference also belong to essence.

But, of course, in particular things the essence has being in an individual.  And when we percieve those individual as individuals – I see Tom - then it is a kind of cognitional being that Tom has in my cognition, over and above the being that Tom has “out there” in the world on his own regardless of my perceptions.

Chapter 4: Essence as found in separate substances

(1) Now let’s see how essence can exist in separate substances, by which is meant human sould, intelligences (or angels) and the first cause (namely, God).

Everyone, of course, admits that the First Cause, God, is simply in nature without any composition in any way whatsoever.

But beyond that there is much disagreement about the nature of intelligences (or angels) and human souls, with some people saying that in a way, all things except God have some sort of matter.

Bus separate substances are immaterial and here’s proof from the power of the understanding:

Forms are actually intelligible only when separate from matter and its conditions; but this actual intelligibility comes only when they are received into a mind by power belonging to an intelligent substance which receives them and acts on them.  Therefore, every intellectual substance has to be free of matter to receive forms in this intellectual way.

(2) It isn’t just a kind of corporal matter that might prevent intelligibility of a form, because corporeal matter is just matter having a corporeal form.  And this corporeal form, like any form, is actually intelligible insofar as it is abstracted from matter.

Therefore, human souls and intelligences (or angels) don’t have in themselves the composition of matter and form, although they do have a composition of form and being (esse).

(3) How can this be?

Well, if one thing is a cause of the being of another, then the first can exist without the second, although not vice versa.

Now, form gives being (esse) to matter (as we saw in Aritotle), so matter cannot exist without form, although it is conceivable that form exist without matter.

And we might say that forms without matter are in some sense closer to God who is most simple and who is pure act.  And these forms or beings close to God are called intelligences or angels.

There’s no necessity that their essences be anything else but form.

(4) The essence of a composite substance, then, has form and matter, which the essence of a simple substance is form alone.  So,

1) The essence of a composite can be signified as part or whole, which the essence of a simple substance can only be signified as a whole, because it is only form. 

(5) and 

2) essences of composites are multiplied such as angels or intelligences have no matter at all, so there can’t be many individuals in each species.  Therefore, there are as many species as individuals.  We might say angels or intelligences differ in species the way dogs and cats differ in species, although for angels this is their individual natures.

(6) But of course, these pure forms are not absolutely simple, they are not absolutely and purely just act of being, but rather they have some potentiality or potency.

Consider essence.  Anything not contained in it is extrinsic in some sense and comes fro outside its notion.

But essence can be understood without knowing how that essence exists, how it has being, or knowing anything about its being.

So being (esse) is other than essence or quiddity, unless somehow there is a being whose essence is its being (esse).

Such a thing would be unique, of course.  It would have no difference, no matter and no distinction between receiver and received.

It would be subsistent being, Being Itself without addition of form.

All else would be either, form and being or form and matter and being.  It alone would be pure being, pure act of being or pure act of existence.

(7) This being (esse) comes from outside essence and is what makes essence actually exist.

And everything which is such that its being (esse) is distinct from its nature or essence, must get its being from another source.

That other source must be what causes being for all other entities; it must not merely have being as part of it, but rather it must be itself pure being which is not restricted or delimited by any form, it must be the absolutely first cause of all, God.

(8) Every receiver is potential with respect to what it can receive and what is received in it is its actuality.

(The radio receiver is able to receive the transmission from the station [= is potential with respect to what it can receive] and the transmission received in it is its actuality or actualization as what it is in act or when fully working, namely a radio receiver.)

The essence then as quiddity or form in the intelligence or angel must be playing the role of potency to receive the being or act of existence (esse) from God who causes it actually to exist.

So, in a way, there is potency and act in the intelligences.  But, if you feel that you must use the terms matter and form to describe these, well, OK, but you have to realize that you are using these terms wrongly or at least not properly, that is to say you are equivocating.

(St. Bonaventure and others wanted to do this, but Aquinas thought it was just bad philosophy to do this.)

All these notions “to suffer,” “to receive,” “to be in a subject,” etc. which are all expressions which seem to be attributed to things because of matter, but in fact they can be used of intellectual substances as well as corporal substances.  But when you do that, you are equivocating, because they do not have exactly the same meaning when used of intellectual substances as when used of corporal (bodily) substances.  So be careful!  Equivocation is OK, as long as you know exactly what you mean when you used the words in their different senses.

(9) Now, remember we said that an intelligence is a pure form without matter, that is, it is an essence which is only form and this is the whole and complete answer to the question, what is it?  But, while that form or quiddidy (+ whatness) or essence is identical with that which it is, still it needs its being (esse) which is that by which it subsists in reality – and this being (esse) is received from God.

So we could say with some people that a substance such as an intelligence is composed of “that by which it is” and “that which is,” or similarly we can follow Boethius and say it is composed of “that which is” and “being” (esse).

(10) (Don’t worry over what the Commentator, Averroes, says.)

These separate substances are distinguished from one another by degree of potency and act.  Those which are closer to God who is pre act themselves have more act and less potency than those more distinct from God.  There is a hierarch then.

Now, among the separate substances, the human soul which is indeed an intellectual substance has the lowest place on the hierarchy.

What is the nature of the human soul as intellectual substance?  As Aristotle says in his Psychology (De Anima), the possible intellect which is where the intelligible forms or intelligible structures of things are received when we know, this possible intellect is open to all reality and is like a blank tablet on which nothing is received, a tablet ready to receive any intelligible form.

Yet, the human soul is so low on the hierarchy that it shares its being such that the soul and the body make one being in one composite substance.  Here, however, the soul does not depend on the body for its being (esse) but rather the body depends on the soul to communicate being (esse) to the body.  So closely united are they, however, that soul uses the senses of the body as the soul works to fulfill itself in knowledge.

After the human soul and body, we find other forms as well.  But unlike the human soul which is the form for the human body and which can exist apart from the body, lower forms cannot exist without matter.

Ch. 5:    Essence as found in different beings.

(1) Let’s recapitulate and expand a little on what we’ve seen so far in this treatise.

     Now there are three ways that substances can have essence: where

(1) essence is perfectly identical with being (esse), existence) as in God.

(2) essence is distinct from being (esse, existence), as in intellectual substances such as

(a) intelligences or angels which are never in touch with matter, or

(b) Human souls which are at least for a time in touch with matter by being in a 

      body

(3) essence is distinct from being (esse), but the essence is necessarily always a 

      composite of matter and form and neither can ever exist apart, as in dogs, cats, 

      flowers, water, etc.

(A) God, we can say, is a reality whose essence is his very being (esse).  In a sense, then, he does not have a quiddity or essence, because his essence is his being (esse).  And if he has no quiddity or essence, he has no limiting form to make him finite and to place him in some genus.

(2) God is pure being, only being (esse tantum).

Now, does this mean that God is the being of all things?  Are all things just parts or accidents of one being which is God?  Someone under the influence of Parmenides might say this, because outside being nothing is!   To be outside of being is really not to be part of being!  This approach seems to say that there is some sort of universal being which is God and that other things don’t really have their own beings, but rather they are just additions and modifications of Divine Being or What is (esti).  This would mean that being is a sort of universal being which is God and that other things don’t really have their own beings, but rather they are just additions and modifications of Divine Being or What is (esti).  This would mean that being is a sort of universal form which all must first participate before things can become anything definite.

But this is misconceived.  Universal being is a conception of the mind as are all universals.  What exists are beings which are different from one another because eaach has its own being, each is its own individual substance or being.

What of God?  God is pure being without any addition.  As pure, it is being radically distinct form all other sorts of being and individuated by its purity.

The conception of universal being does make sense as an abstraction of the mind.  But it makes sense only as an abstraction which does not prescind from (= does not absolutely leave aside) an addition which in reality determines it as being in a particular.  That is to say, this universal being must be a notion that indeterminately and indefinitely does contain all the additions that can be made to it in specifying the kinds of beings.

Why? What would happen if this universal being were a notion of being which prescinded from all additions, which in no way included any additions to it to determine it?  What would be the status of the additions?  Are they beings?

If this notion prescinded from addition, we could not conceive anything existing in which there would be an addition to being.  All would be one.

(Additional note: Aquinas says the being of creatures can be called common being (ens commune or esse commune) because it is a notion which allows this addition of genus and species in its determination.  Divine being or God is different because it is absolutely unlimited and all-perfect, pure being, without any addition possible.)

(3) So God is pure being but in the sense that he possesses all perfections manifested in all creatures, although in creatures those perfections are manifested in a lesser way, in him in a much more excellent and exalted way.  In other things perfections are manifested in diverse ways, but in God they are all perfectly united in his one simple being which is identical with his essence.  In that being are found all the perfections that can be had by creatures (and more, of course), although in God they exist in a much more exalted way which our human reason cannot fully grasp or express through language of any sort.

(4) (2) In created intellectual substances, essence is found as distinct from being (esse).

In these substances separate from matter being is received and “is limited and restricted” in accordance with the essence of the receiver, that is to say, it is “restricted to the capacity of the recipient nature.”

For intelligences (=angels) which are always separate from matter, this means that their forms limit the being they receive from a higher reality (=God) but are not limited from below as they would be if they had matter.

(5) These intelligences are each an individual separate species, then, since they can have not matter.

But what of the human soul?  How does it get its individuality?  

How is it that it does not lose its individual being when it’s separated from the body?

Since humans are composite entities, they have their very existence as composites.  The soul is the life source form the body and the two together make one living human person.  The person acquires his individuality at the moment of his coming into being as a real composite being which exists as a unity of soul and body.  But the soul is an intellectual substance which indicates that it does not need the body for all its operations or activities.  In fact, we’ve seen that the soul is the form and the form communicates actual existence or being to the body when the two are one composite being.  ((Remember this is not a question of the soul or form existing before the body in time.  Rather, the priority is one of nature, not time.))

If that is so, then after the soul and the body are made to exist as one composite actually existing being, it remains possible that the soul exist without the body.  Yes, Tim is one composite of soul and body, but since part of him – namely the soul – seems to be intellectual and separable from the body (because of the operations it can perform without the body), and since it is conceivable that the soul has a separate being, once the soul has acquired its individuated being by having been made the form of a particular body, that being always remains individuated.”

(6) Furthermore, substances whose quiddities are not identical with their beings can be classified in categories.  So genus, species and difference apply to them.

OK, I know it’s not possible for us to know absolutely and perfectly the essential differences of sensible things, but we can get some grasp of what they are through the accidents they cause in things.

For immaterial substances, however, we just don’t know the proper accidents, so we can’t get at their real differences or even accidental differences.

(7) Genus and difference are derived in different ways in sensible substances and immaterial substances.  In immaterial substances which are simple essences or simple quiddities, the difference is taken from the whole essence or quiddity.  In sensibles, what is called a “simple difference” can be taken from the form, but what form is only part of the quiddity or essence. ((That’s why we say “simple difference”.))

(8) What about the genus of immaterial substances?

Separate substances are alike in being immaterial and they differ in degree of perfection.  So then we might derive the genus from what follows as a result of their immateriality, namely their intellectual characters.  The difference which is derived from what follows upon their degrees of perfection, though, is unknown to us.

(9) In these things which are separate forms, different degrees of perfection in their forms, different degrees of perfection in their forms produce necessarily different species.

(10) (3) Essence in things whose very existence is always had as composites of matter and form also involves the reception and limitation of being (esse) which they receive from another source (=God).  Here designated matter makes possible the plurality of individuals in one species.