Essence, in the Thomistic View

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(From De Ente et Essentia)
(I made use of the LEONINA edition)


Much of the following is already treated of elswhere on this website, but here we concentrate (even more) on the view of St Thomas.
After all, the Essays try to be a little independent from each other (that's why I call them 'Essays'). Moreover, because the subjects treated of are somewhat difficult and abstract, it is probably not superfluous to repeat their treatment here and there, in different contexts, resulting in a consolidation of them in the mind.

The ESSENCE of a thing, is : WHAT the thing intrinsically is. With "a thing" is here meant : An individual Totality, an individual uniform being. The mentioned "WHAT" does not relate to that individual thing insofar as it is individual -- when it does so relate, then we have to do with the PERSONAL (See NOTE 1) -- but relates to its specific identity, and as such it can serve as a point of reference to which the per se and the per accidens can relate, i.e. some feature of an individual could be, say, per accidens, which means per accidens with respect to its Essence, and this in turn means that the feature is not necessarily implied or caused by the Essence of that individual being.

In the First Series of Essays of this Website I established the whereabouts of Essence (The Essence of a thing), based on modern insights, especially dynamical systems : The Essence of a thing is the Dynamical Law of that Dynamical System that has directly generated that thing, or could, in a direct way generate that thing.
Because the present Essay belongs to the Second Series it will put less emphasis on this assessment of Essence, but will concentrate more on classical ideas about it, especially those of St Thomas Aquinas.

St Thomas' View of Essence

In Chapter 1 of the treatise De Ente et Essentia St Thomas enumerates some views about Essence, and concludes by saying :
"But it is called essence insofar as by it and in it a being has existence."
Essence is of course (also) Whatness, but is over and above that also something that confers in one way or another existence (being).
In Chapter 2 St Thomas states that in (ontologically) composed substances is form and matter, like, he says, in man soul and body.
The Essence is signified by the definition of the thing (and that is the definition of the species). And in order that natural things can, in their definition, be distinguished from mathematical objects, not only the form, but also the matter, must be represented in that definition. Matter belongs per se to the Essence of a substance, not as something added, i.e. not an 'ens extra' ( = an extra being ).
But the real cause of the being of something is (at last) the form.
The matter in this Essence does however not already make this Essence individual. The thing does not become individual until by designated matter ( = matter considered as designated), the materia signata. And this designated matter is, according to St Thomas (De Ente et Essentia, Chapter 2, line 75) matter-considered-under-determined-dimensions. This designated matter is not represented in the definition of, for example, man as man, but would be represented in the definition of Socrates, if Socrates had a definition. The definition of, say, man, represents -- still according to St Thomas -- (besides the form) the non-designated matter, materia non signata :
"The definition after all does not represent these bones and this flesh, but bones and flesh [ taken ] in an absolute way, which constitute the non-designated matter of man."
The Essence appears in our knowledge (i.e. the Essence as known) as the definition, and this definition consists of genus and difference. Together, and undifferentiated, genus + difference form the species, and also the latter is the Essence-as-known.
The genus is taken from the material part of the thing, but does not signify that part. The genus signifies the whole, whereby the possible formal parts are only implicitly contained in the genus. The same applies to the difference : the difference is taken from the formal part, but does not signify that part, but the whole. So the difference 'rational' means : something that has a rational soul. Thus the material part is not excluded, it is indicated, be it only in an indeterminate way.
"And from this the reason is clear in what way genus, species and difference relate proportionally to the matter and the form and the composite among natural things, although they are not identical with them : because neither the genus is matter, but taken from matter, in order to signify the whole, nor the difference the form, but taken from the form, in order to signify the whole."
(De Ente et Essentia, Chapter 2, line 195--200)

The unity of the genus does not imply the presence of one Essence in the different species of that genus. The unity of the genus is caused by its indeterminateness : when the possible differences are added then that indeterminateness disappears and so that unity, resulting in the different species of that genus. About the same relation as with genus to species, holds in the case of species to individual.
The species expresses the whole, but, in expressing so the individuation conditions are only implicitly contained. Because of expressing the whole the species can be predicated of an individual : Socrates is a HUMAN BEING.
But if the content of the species is expressed under a cut-off of designated matter ( = matter insofar as it is designated), thus with a (accompanying) cut-off of the individuation conditions, then the content of the species is expressed as a part, for example with the term HUMANITY (human beingness, humanitas ). And such a term cannot directly be predicated of an individual. We cannot legitimately say : Socrates is humanity. What we can say is just this : Socrates has humanity (meaning Socrates having a human nature).
Matter as designated ( materia designata) does not belong to those factors by virtue of which a HUMAN BEING is a HUMAN BEING (according to St Thomas, De Ente et Essentia, Chapter 2, line 257--260).
The species, considered under the cut-off of the designated matter, is however still composed (of matter and form). But despite the fact that, say, HUMANITY ( = the species, considered under cut-off of the designated matter) is composed, it is not the same as MAN, HUMAN BEING ( homo ), because HUMAN BEING contains, although implicitly, the individuation conditions. This HUMANITY consequently must be received by something, and that something is matter insofar as designated. That, from which the content of the species is taken is the meaning of the term HUMANITY in which the designated matter is excluded from consideration. In this way the content of (the concept of) HUMANITY refers to a formal part of the thing (in this case of a human being). And so HUMANITY is a kind of form, and St Thomas calls this form "the form of the whole" ( forma totius ), i.e. a 'form' consisting of matter and form. The matter in this forma totius is the same matter as the matter in : "designated matter", but now considered as not (yet) designated. This forma totius St Thomas contrasts with an added form, like the form of a house. This form is added to the material, i.e. to the material parts which are formed into 'house'. The cause of this last mentioned 'forming', is extrinsic (it is in the builder). It is a forming-over (in-formation) of already in-formed matter, as is also the case with the creation of a statue out of marble.
The forma totius however is intrinsic and is not 'added' by an external cause. The house or the statue is a whole per accidens, while a human being is a whole per se, and also HUMANITY, albeit under cut-off of individuation conditions. Accordingly St Thomas says (in De Ente et Essentia, Chapter 2, line 290--304) :

"And so it is clear that this name human being [homo] and this name humanity [humanitas] signify the essence of man, but in different ways, as has been said : because this name homo signifies that [ essence ] as a whole, insofar as it does not leave out of consideration the designation of matter, but containing it implicitly and undistinguished, like it was said that [ also ] the genus contains the difference. And this is why this name homo is predicated of the individuals. But the name humanitas signifies it [ = the essence of man ] as a part, because it [ = the name humanitas ] contains in its signification [ = in its meaning ] only that which belongs to man insofar as man, and [ with it ] leaves out of consideration any designation [ = delimitation of matter, matter as designated, and thus the individuation conditions ]. Thus it [ = the name humanitas ] is not predicated of the individuals of man. And that's why one sometimes encounters the name of the essence being predicated of the thing. After all we say that Socrates is some essence [ We then say : Socrates is a human being ]. And sometimes it is denied, when we say that the essence of Socrates isn't Socrates [ Because we do not say : Socrates is humanity ]."
So, with respect to man, HUMAN BEING refers to the forma totius (= Essence) of any individual representing the species HUMAN BEING, but it refers to it as a whole, while HUMANITY refers to that same forma totius, but now (refers to it) as a part, by explicitly excluding all individuation conditions. When we (while abstracting still further) only, and exclusively, refer to the formal content of the Essence, and thus refer to an incomplete essence, we refer to the forma partis. I assume that for this case we can also use the term HUMANITY.

'Substance' is often used in Thomistic texts to denote the Essence, for example in "substantia rei" ( = the substance of the thing). But often it also means : the individual thing that stands on itself (i.e. that is ontologically independent). Thus 'substance' not only refers to the Whatness of the thing, but also to the way of being, namely a not-to-be-in-something-else.

We have treated of the individuation conditions, represented by the materia signata (sometimes also denoted by materia designata), that is matter considered under the aspect of delimitation, and this in turn means, matter considered under the aspect that it is (because of that delimitation) so an so much (i.e. so much matter is in Socrates, and so much in Fido (the dog), etc.). Matter thus can be considered as relating to several aspects, which can be manifested by it in given cases :

  1. Matter as Prime Matter.
  2. Matter as quantified.
  3. Matter as not designated (not delimited). (NOTE 2).
  4. Matter as designated.
Matter as designated ( designata or signata ) presupposes matter as quantified, to which is (when we consider the matter as designated) added : actual circumscription (delimitation) to so and so much.
Matter as quantified just means matter as three-dimensionally extended (that's all what it means in the present context).
Matter as designated means matter as three-dimensionally extended and actually designated (delimited) to precisely so much.
Matter is in itself indivisible, but becomes divisible by its being quantified. Next it can be actually divided into individuals of the same species (matter-parts, which each for themselves possess a form, which is identical in content with the remaining forms which are alotted to those other matter-parts). And in this way an Essence resides in matter (in which, consequently, the matter of "in matter" is matter insofar as designated).
(See BOBIK, J., 1965 (1970), Aquinas on Being and Essence, p. 148.)

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