[4.14.4] Henry of Ghent on Intentional Distinction of Essence and Being

Henry of Ghent (“Doctor Solemnis”, 1217?, d. 1293 AD) in Quodlibet II, q. 8 and V. q. 6 writes about ontology by analyzing the relation of thing, essence and being (existence):

  • He agrees with Avicenna (see [3.3.1]) that every thing (res) possesses its essence (quidditas), which differs from its being (existence).
  • An essence can be considered in itself, independently of its physical (or mental) existence. This means that being is not part of its content, so the essence – being distinction is not based on reason alone. 
  • On the other hand, being includes the concept of essence. “Being and essence are therefore different intentions, not different things.” So we have an intentional distinction between essence and being.
  • Essences have a natural tendency towards non-being. Their existence depends on God’s creative and supportive act.

The following OntoUML diagram presents Henry of Ghent’s ontological model:

Henry of Ghent on intentional distinction of essence and being in an external (material) thing
ClassDescriptionRelations
ThingAn enduring external material substance, a thing (res).
Essence“For Henry (as for Avicenna) every res possesses its own “certitude” (certitudo) that makes it what it is. Certitudo here means stability, consistency, and ontological self-identity: a triangle is a triangle and nothing else, white is white and nothing else. 
Certitudo thus expresses the objective content by which every thing is identical to itself and is distinguished from other things; in other words, certitudo expresses the essence or quidditas of a thing (“unaquaeque res habet certitudinem propriam quae est eius quidditas” — “every thing possesses its own certitude, which is its essence”). This content can be considered in itself, as independent from its physical or mental existence. In an absolute sense, every essence possesses a double indifference: with regard to actual existence or non-existence (essence in itself is simply possible), and with regard to universality and particularity. These last two aspects are really conjoined. Essence is particular in that it receives its subsistence in a given suppositum (concrete individual entity) from something-other-than-itself, while it is universal in that it is abstracted by the intellect from these singular supposita, in which it exists as one in many, in order to become predicable by many.
Yet in itself essence is just essence: “essentia est essentia tantum”. Even though for both Avicenna and Henry thing (res) and being (ens) are primary notions (or rather intentions — intentiones — the sense of which we shall soon clarify), intentio de re seems to have a certain precedence over intentio de esse, at least logically, in virtue of its double indifference.
shared part of Thing
Accident“anything that belongs to a thing, being external to the intention of its essence, can be called an accident.”exclusive part of Thing
Being“We still need to clarify in what sense existence can be said to be concomitant with essence. Being has access to essence from the outside, in the sense that it does not strictly belong to the essential nature of a res, except in the case of God.
If this were not the case, a thing (every thing) would not simply be possible in itself, but necesse esse (necessary being) on a par with God. Instead, being seems to be an accident, or rather it has almost the mode of an accident (Quodl. I, q. 9). Nevertheless, it is not an accident in the real sense, since it is not added to something pre-existing, but is rather that by virtue of which a thing exists. In other words, we cannot refer here to the Aristotelian definition of accident (that which has its being in another thing or inheres in a subject), but once again to the broader definition given by Avicenna, according to which anything that belongs to a thing, being external to the intention of its essence, can be called an accident (“Sed intelligendum quod ‘accidens’ accipitur hic largissime, secundum quod iuxta modum loquendi Avicennae ‘accidens’ rei appellatur omne quod convenit ei et est extra intentionem suae essentiae”; Quodl. II, q. 8, ed. Wielockx, p. 48, ll. 21-23). In this sense an accident is anything that is external to the intentio of a res as absolute essence, without ever being really distinct from it. With regard to essence, actual being (that is, ratio suppositi) represents an accident of this type. Being is therefore an intentio that occurs to essence without adding anything real, and so it differs from essence only intentionally.”
charaterizes Essence
TendencyTo Non-Being“every creatural essence tends naturally toward non-being [tendency to non-being] (in Avicennian terms, no possible essence, in the absence of a cause for its existence, could exist), though this inclination can be reversed by an external cause.
No essence of a thing is so rigidly oriented toward nothing that it cannot receive being-in-act through a divine action. Similarly, even when placed, in act no thing ever possesses its being in an ultimate way: if God were to withdraw His support, it would fall into non-being.”
charaterizes Essence
IntentionalDistinctionBeing and Essence according to Henry are the same thing,
“While two distinct things differ in a real sense, all that gives rise to different concepts, albeit founded in the same simple thing, differs intentionally (“diversa intentione sunt quae fundata in simplicitate eisudem rei diversos de se formant conceptus.”; Quodl. V, q. 12, ed. 1518, f. 171rT). In an intentional distinction, in other words, the very same thing is expressed by different concepts in different ways. From this perspective, an intentional distinction seems akin to a purely logical (or reasoned) distinction, to the point that the two are often confused (“frequenter intentio ratio appellatur.”; Quodl. V, q. 12, ed. 1518, f. 171rV). Nevertheless, in the first case, one of the concepts excludes the other (one can be thought of separately, in the absence of the other), whereas in the case of a distinction based on reason the various concepts are perfectly compatible (“in diversis secundum intentionem unus conceptus secundum unum modum excludit alium secundum alium modum, non sic autem differentia sola ratione.”; Quodl. V, q. 12, ed. 1518, f. 171rV). As Henry explicitly states, this means that everything that differs in intention differs in reason too, but not vice versa. Unlike a purely logical distinction, an intentional distinction always implies a form of composition, even though this is minor with regard to that implied by a real difference. […]
The distinction between being and essence belongs to the last mode [intentional distinction]. Since being is not a real accident inhering in a subject, it makes no sense to speak of a real distinction. Instead, the distinction depends on the fact that the intellect uses different concepts to indicate the being of a thing, on the one hand, and that which a thing is, on the other.
Nevertheless, since essence can be thought of independently from its being, and being is not part of its content, we cannot refer here to a distinction based on reason alone. In other words, whereas the concept of actual existence always includes the concept of essence, the contrary is not true, since essence can be thought of without its being (as affirmed by Avicenna). Being and essence are therefore different intentions, not different things (as instead was maintained by Giles of Rome in his long dispute with Henry). This intentional distinction is in itself sufficient to refute the conclusion that every essence is its being.”
relates Being and Essence
GodMonotheistic Godprovides and supports Being

Sources

  • All citations from: Porro, Pasquale, “Henry of Ghent”The Stanford Encyclopedia of Philosophy (Fall 2014 Edition), Edward N. Zalta (ed.)
  • Pickavé, Martin, “Henry of Ghent on Individuation, Essence and Being”, A Companion to Henry of Ghent, Brill, 2011, Gordon A.Wilson (ed)

First published: 25/3/2021

[4.9.4] St Thomas Aquinas on the Classification of Sciences

St Thomas Aquinas ( “Doctor Angelicus”, 1225 – 1274 AD), in his book On The Divisions and Methods of the Sciences: Questions V and VI of his Commentary on the De Trinitate of Boethius writes about the division of sciences (see also [1.3.10])

  • Sciences can be speculative or practical, depending on their relation to truth. Speculative sciences contemplate, while practical sciences apply truth.
  • We can analyze the object of study of the speculative sciences based on their dependence on the existence and understanding of matter and motion.
  • Based on this analysis, the complete list of speculative sciences is physics, mathematics, and metaphysics.
  • Ethics, economics and politics are practical sciences.

The following OntoUML diagram presents Aquinas’s division of sciences:

Aquinas on the division of sciences
ClassDescriptionRelations
Science“There are [..] two distinct classes of science: speculative science and practical science. Speculative sciences are those that contemplate truth whereas practical sciences are those that apply truth for some practical purpose. The sciences are then further distinguished through differentiating their various subject-matters.”studies SubjectMatter
Understanding“Working within the Aristotelian tradition, Thomas holds that something is understood when it is separated from matter and is necessary to thing in some respect. For instance, when we understand the nature of a tree, what we understand is not primarily the matter that goes to constitute the tree in question, but what it is to be a tree, or the structuring principle of the matter that so organizes it and specifies it as a tree rather than a plant. Furthermore, assuming our understanding is correct, when we understand a thing to be a tree, we do not understand it to be a dog, or a horse, or a cat. Thus, in our understanding of a tree, we understand that which is necessary for the tree to be a tree, and not of anything that is not a tree. Hence, our understanding of a thing is separated from its matter and is necessary to it in some respect. Now, what is in motion is not necessary, since what is in motion can change. Thus, the degree to which we have understood something is conditional upon the degree to which it is separated from matter and motion. It follows then that speculative objects, the subject-matter of the speculative-sciences, insofar as they are what are understood, will be separated from matter and motion to some degree. Any distinctions that obtain amongst speculative objects will in turn signify distinctions amongst the sciences that consider those objects; and we can find distinctions amongst speculative objects based upon their disposition towards matter and motion.”relates between Science and SubjectMatter
PracticalSciencepractical sciences are those that apply truth for some practical purpose.”subkind of Science; applies Truth
Ethics; Economics PoliticsEthics, economics and politics are practical sciences.subkind of PracticalScience
SpeculativeScienceSpeculative sciences are those that contemplate truth […]
There are three divisions that can apply to speculative objects, thereby permitting us to differentiate the sciences [to physics, mathematics and metaphysics…]
Thomas takes this division of the speculative sciences as exhaustive. For Thomas, there could be no fourth speculative science; the reason for this is that the subject-matter of such a science would have to be those things that depend on matter and motion for their being understood but not for their being, for all other combinations have been exhausted. Now, if a thing depends on matter and motion for its being understood but not for its being, then matter and motion would be put into its definition, which defines a thing as it exists. But if a thing’s existence is so defined as to include matter and motion, then it follows that it depends on matter and motion for its being; for it cannot be understood to be without matter and motion. Hence, all things that include matter and motion in their definitions are dependent on matter and motion for their being, but not all things that depend on matter and motion for their being depend on matter and motion for their being understood. There could be no fourth speculative science since there is no fourth class of speculative objects depending on matter and motion for their being understood but not for their being. Thomas thus sees this threefold division of the speculative sciences as an exhaustive one.”
subkind of Science; contemplates Truth
Physics“(i) physical science considers those things that depend on matter and motion both for their being and for their being understood”subkind of SpeculativeScience; studies ObjectOfStudy OfPhysics
Mathematics “(ii) mathematics considers those things that depend on matter and motion for their being but not for their being understood”subkind of SpeculativeScience; studies ObjectOfStudy OfMathematics
Metaphysics“(iii) metaphysics or theology deals with those things that depend on matter and motion neither for their being nor for their being understood.”subkind of SpeculativeScience; studies ObjectOfStudy OfMetaphysics
SubjectMatter“In order to ascertain the subject-matter of any particular science, Thomas distinguishes between the different intellectual operations that we use when engaged in some particular scientific endeavor. Broadly speaking, these fall into two categories: the speculative and the practical. Concerning some sciences, the intellect is merely speculative  by contemplating the truth of some particular subject-matter; while concerning other sciences, the intellect is practical, by  ascertaining the truth and seeking to apply. There are thus correspondingly two distinct classes of science: speculative science and practical science. Speculative sciences are those that contemplate truth whereas practical sciences are those that apply truth for some practical purpose. The sciences are then further distinguished through differentiating their various subject-matters.”
ObjectOfStudy OfPhysics“(i) there is a class of speculative objects [object of study of physics] that are dependent on matter and motion both for their being and for their being understood, for instance, human beings cannot be without matter, and they cannot be understood without their constituent matter (flesh and bones)”subkind of SubjectMatter
ObjectOfStudy OfMathematics“(ii) there is a class of speculative objects [object of study of mathemathics] that depend on matter and motion for their being, but not for their being understood, for instance, we can understand lines, numbers, and points without thereby understanding the matter in which they are found, yet such things cannot be without matter”subkind of SubjectMatter
ObjectOfStudy OfMetaphysics” (iii) there is a class of speculative objects [object of study of metaphysics] that depend on matter and motion neither for their being nor for their being understood.
[…] As it is a purely rational science, not dependent on or presupposing the truths of revelation, metaphysics will be a study of the neutrally immaterial aspects of things, that is, a study of those modes of being that apply to all beings, whether they are material or immaterial. 
Thomas does not adopt the Aristotelian phrase (being qua being) as the subject-matter of metaphysics, he offers his own term. According to Thomas, ens commune (common being) is the proper subject-matter of metaphysics. Through an investigation of ens commune, an investigation into the aspects of being common to all beings, the metaphysician may indeed come to a knowledge of the causes of being and might thereby be led to the affirmation of divine being, but this is only at the end of the metaphysical inquiry, not at the beginning.”
subkind of SubjectMatter

Sources

  • All citations from:  Kerr, Gaven : “Aquinas: Metaphysics”Internet Encyclopedia of Philosophy
  • McInerny, Ralph and John O’Callaghan, “Saint Thomas Aquinas”The Stanford Encyclopedia of Philosophy (Summer 2018 Edition), Edward N. Zalta (ed.)
  • The Cambridge Companion to Aquinas, CAMBRIDGE UNIVERSITY PRESS, Edited by  Norman Kretzmann and Eleonore Stump, 2010

First published: 01/10/2020