Hilary of Poitier's Argument For Human & Divine Equality
[I was a bit under the weather and very busy this week, so instead of taking the time and effort to flesh out one of my existing column ideas, I decided to just write up what I've been immediately thinking about lately. As it turns out, I've been thinking a lot about Hilary of Poitier's doctrine of equality.
Hilary of Poitiers is a Doctor of the Church of the 4th century AD, known mostly for his stand against Arian doctrine. He played a big role in my dissertation, and ever since then, I've been fascinated by his concept of (human and divine) equality, which he makes absolutely central to both his theology and anthropology. Since then, I've been working on a paper on the topic, and trying to puzzle out both his essential argument, and especially what his sources and influences might have been. I haven't solved the latter one quite yet, but I thought it might be helpful to try to flesh out and write out in my own words what I take to be his essential argument and definition of equality.
(It's sad to think how many people in the modern world don't realize that the centrality of equality in Christianity and modernity ultimately traces back to 4th century Trinitarian theology in general and Hilary of Poitiers in particular!)
The below, then, is based on Hilary's work, especially De Synodis, with a smattering of De Trinitate, Ad Constantium, and In Constantium; it includes a few quotations from De Synodis at key points. However, while I believe the main arguments and conclusions are Hilary's, it also includes my own attempt to think through the implications and possible additional arguments and defenses for his concepts. Probably no one will find this interesting, but I enjoyed writing it. Ora pro nobis!]
I. That All Human Persons Are Equal, and Are Defined by Relations of Equality
(1) Postulate: The fundamental, basic category of experience and philosophical reflection is res: that is, "a thing" or "a reality."
(2) Postulate: res can only be spoken of and made the subjects of philosophical thought to the extent that they exist and are rationally comprehensible.
(3) Argument: "Essentia (=ὀυσία, essence), and natura (=φύσις, nature), and genus (=γένος, natural kind), and substantia (=ὑπόστασις, substance), are able to be predicated of every res whatsoever."
(4) Definition: "An essentia (=ὀυσία, essence), is a res which exists, or it is those things from which a res exists, especially a res which stably exists (subsistit=subsists) in that which is enduring. Most properly, however, a res is called essentia insofar as it always exists." (De synodis 12)
That is to say, essentia designates a thing, a reality, insofar as it truly exists, and therefore insofar as it endures stably and in an orderly and knowable fashion over time. In particular, it describes a res insofar as it is either actually capable of, or at least tends toward, perpetual, ongoing existence. All res that possess essentia therefore in some sense tend towards perpetual existence.
(5) Definition: "The res, therefore, is also a substantia, because it is necessary that the res which it is should stably exist (subsistit=subsists) in itself." (De synodis 12)
That is to say, substantia (=ὑπόστασις, substance) designates a thing, a reality, insofar as it stably exists in and of itself. In this sense, substantia is not strongly distinguished from essentia: both designate a res insofar as it exists stably in such a way as to tend toward perpetual existence, with essentia describing this in terms of being and substantia laying the emphasis on stability and enduringness and their containment within the res itself.
(6) Definition: "Whatever stably exists, without a doubt is enduring in its genus or natura or substantia. When, therefore, we speak of essentia in order to signify nature or natural kind or substance, we understand them as belonging to that res which always stably exists in all these things." (De synodis 12)
Genus, natura, and substantia, then, are all essentially aspects of essentia, ways of designating and further describing those aspects or elements of a res by which it is enabled to exist stably in a way tending toward perpetual existence.
(7) Context: From among these terms, focus in on natura (=φύσις, nature). The Greek φύσις is etymologically tied to concepts of "birth" or "origination," as well as to broader ideas of "growth," "life," "movement," "springing up" (a la plants), and so forth. Natura, however, is derived from the more limited Latin word nascor="to be born, to be produced, to be procreated."
In speaking of natura, then, Hilary specifically intends to zero in on the aspect of a res's continuing existence that are tied to origination in general and procreation in particular.
(8): Argument: Among those aspects of essentia that allow a res to exist stably in a way tending toward perpetual existence, central to many of our experience is the fact that the res was itself procreated by a res of the same genus and natura, and it in turn possesses the capability of procreating another res of the same genus and natura.
(8.1) This is especially important for res like animals or human beings existing in time, and so in at least some aspects impermanently.
(8.2) For res such as these, without procreation, in a very short time there would be no animals or human beings in actual existence, and so by necessity human being and animal would not be rationally comprehensible or knowable res.
(8.3) Furthermore, without procreation, humans and animals would be fundamentally temporary and transitory res, not in any genuine way tending towards perpetual existence, and so not describeable in terms of concepts like essentia and substantia. These res would not, therefore, truly subsist, and therefore they would fail to exist and to rationally knowable in a fundamental sense.
(8.4) Procreation is therefore metaphysically essential to the existence of these res, and possibly of all res.
(9) Argument: The process of procreation consists of two necessary elements: two entities who are truly distinct, of which one originates the other, and also a single natura which endures through the process of procreation and is shared in toto by both entities.
(9.1) If the two entities were not truly distinct, there would be nothing to distinguish natura from the simple enduring existence of an entity in itself designated properly by substantia.
(9.2) If the two entities were not truly distinct, then it would be logically impossible, as happens in our experience, for one of the entities to die and cease to exist, and the other to continue existing.
(9.3) Hence, if the two entities were not truly distinct, then procreation would be absolutely useless in ensuring the continuing existence of the res and its tending toward perpetual existence.
(9.4) If, on the other hand, nothing endured or continued to exist through the process of procreation, then procreation would have no relevance for the essentia of the res, and the res would therefore fall afoul of (8) and no longer truly exist or be rationally comprehensible.
(9.5) That the natura is shared in toto by both entities follows self-evidently from the definition of the term (see 10 below).
(10): Definition: Natura designates precisely that aspect of a res which stably exists and endures through the process of procreation.
(11) Argument: Natura must include all substantial and essential and generic properties possessed both by the progenitor and the natural kind as a whole.
(11.1) We in fact find, in our experience, that the offspring of a particular member of a natural kind is of the same natural kind as its progenitor. The child of a human being is a human being, the offspring of a cat is a cat, the offspring of a horse is a horse, and so on.
(11.2) If natura in the offspring lacked any property essential to the progenitor's own existence as a substantia and essentia, then again, procreation would not in fact extend the stable, substantial existence of the res and, per (8), that res would lack substantial existence and not be rationally comprehensible.
(11.3) If natura in the offspring lacked any property essential to its existence as a member of the same natural kind as its progenitor, then that natural kind or genus would lack stable existence and fail to be comprehensible, also as per (8).
(12) Definition: A virtus is a "natural power," that is, a power essential to the substantial existence of a res and included among its essential properties.
(13) Argument: Per (11) and (12), natura also includes the totality of virtus or natural power.
(14) Definition: Equality (=aequalitas) designates the relationship between a progenitor and an offspring, such that the two are both truly distinct (see 9) and share one and the same natura (see 10) and so all essential and substantial properties.
(15) Argument: "Every child, according to natural birth, is the equality (=aequalitas) of its parent." (De synodis 73).
In other words, the relationship of equality is fully constitutive of the existence of both child and parent qua child and parent, such that both child and parent can and must be described and defined, at least qua child and parent, as subsistent (that is, enduring, existing, rationally comprehensible) relations.
(15.1) Given (11) above, the only thing essentially and substantially distinguishing offspring from parent is the relationship between the two, which per (14) is designated by equality.
(15.2) Given that equality involves the true distinction of the two participants (see 9), this relation is all that is necessary to distinguish the two terms of the relation.
(15.3) Given (15.1) and (15.2), the only thing essentially and substantially distinguishing child and parent is the relation of equality. It therefore essentially and substantially constitutes their relation as child and parent.
(15.4) Furthermore, given that the relationship of procreation is fundamentally a relationship of origination, by which one entity produces another, there is a fundamental sense in which that relation constitutes not only the existence of the child qua child, but the existence of the child simpliciter, which is to say, the existence of the child merely as a res.
(15.5) Likewise, given that for the progenitor procreation extends the stable, essential existence of their own res and grants it a substantiality and essentiality otherwise lacking, there is at least one sense in which the relation of equality also constitutes the existence of the parent, not merely qua parent, but qua substance, qua essence, and therefore qua existence in a fundamental sense.
(16) Conclusion: All human persons without exception are equal (=aequalis, ἴσος) to one another in the sense given in (14).
(16.1) All human persons participate in the process of procreation as defined in (9) either as offspring alone or as both offspring and progenitor, and therefore participate in the relation of equality in a constitutive way with at least some other persons.
(16.2) All human persons belong to the natural kind "human being," which is defineable and knowable only in light of the essentia and substantia and natura whose res exists stably and is known through the process of procreation, and therefore through the relation of equality.
(16.2) Per Scripture and Tradition and dogmatic teaching, all human persons without exception are descended from one original human being, and therefore are related to one another through the relation of procreation, and therefore are equal to one another.
Part Two: That This Equality Has Necessary Implications For Society and Politics
(1) Postulate: Societies consist of human persons.
(2) Postulate: Societies and institutions can be said to exist and subsist and therefore be rationally comprehensible only in a manner analogous to natural res.
(3) Postulate: All societies, including political societies, are formed out of entities that are themselves constituted to a large extent by their direct relations as offspring and progenitor, and therefore by the relationship of equality.
(4) Postulate: Per I. above, all societies, including political societies, are formed out of entities that are equal to one another in essence, nature, and natural power (virtus).
(5) Argument: The existence of political, social, or religious offices, institutions, and societies as stably existing, rationally comprehensible entities is likewise necessarily dependent on relationships of equality.
(5.1) The constitutive relationship between child and parent is analogous to the relationship between (political, social, or religious) predecessor and successor inasmuch as both extend the existence of the office, institution, and society over time in such a way as to give it (analogously) substantial, essential existence and make it rationally comprehensible.
(5.2) Therefore, the existence of all political, social, or religious offices, institutions, and societies is dependent for existence, stability, and knowability on the equality of predecessors and successors.
(5.3) Political, social, and religious societies are analogous to natural kinds.
(5.4) Therefore, all political, social, and religious societies exist in a stable and comprehensible fashion only inasmuch as all members without exception share some (analogous) essence in common.
(5.5) Hence, all political social, and religious societies exist and are rationally knowable only inasmuch as the members are equal to one another.
Part Three: That God is Defined by Equality Between the Persons of the Holy Trinity
(1) Postulate: God may be defined as a res that exists and subsists in the maximal way, such that he not only tends toward, but actually achieves, eternal, stable existence and total rational knowability.
(2) Postulate: Therefore, God may be defined as the only res for which res is absolutely synonymous with essentia and substantia.
(3) Postulate: Given (1) and (2), there is a direct relationship between God and the fundamental metaphysical categories ascribeable to all res, and therefore it is both possible and fruitful to reason about God by analogy from created beings and natural kinds, especially human persons.
(4): Argument: Given the above, and given that as established in I. natura is fundamentally synonymous with essentia and substantia, and given that, as Hilary argues in I.3 above, natura, like essentia and substantia, is able to be predicated of every res whatsoever, it is reasonable that God be equated with natura also, and therefore be defined necessarily by a procreative relationship.
(5) Argument: In applying the terms Father and Son to God the Father and God the Son, the Scriptures and Tradition intend to assert that the necessarily concomitant sense of equality described in (I.14) is the defining feature of the relationship between Father and Son.
(5.1) God is incapable of deliberate deception, and aims fundamentally at the salvation of all human persons.
(5.2) Given (5.1), God uses in their natural significations the essential words of the Sacraments necessary for salvation.
(5.3) The confession of God as Father, Son, and Holy Spirit belongs to the necessary words and actions of the Sacrament of Baptism and therefore is necessary for salvation.
(5.4) Therefore God in designating himself as Father, Son, and Holy Spirit is using the terms "father" and "son" in their natural significations: that is, to designate fundamentally the relationship of natural equality. (See Ad Constantium)
(5.5) Moreover, the Scriptures (Philippians 2:6-11, John 5:18) in fact designate the relation between Father and Son by the term equal (=aequalis, ἴσος), and in Philippians connect this with being "in the form (=essentia, οὐσία) of God," while in John this is treated as the logical, natural consequence of Christ "calling God his Father." (See De Trinitate)
(6) Argument: If the Father and Son are in fact equal in even an analogous sense to that given of human persons in I., they are necessarily equal in a maximal, absolute sense, inapplicable to any other entities.
(6.1) Since Father and Son by procreation share a single natura that includes all essential properties, and since in God there is no distinction between res and essentia, the natura conveyed to Son by the Father in the process of procreation necessarily makes the Son God in the fullest possible sense.
(6.2) Besides substantial and essential properties, all created res possess various accidental properties, which lead to differences among human persons that are not rooted in substance and essence.
(6.3) God does not possess any accidental properties; hence, it is impossible for Father and Son to differ in any way whatsoever.
(6.4) In particular, since virtus or natural power is an essential property, and since all accidental powers or accidental differences in the exercise of natural powers are excluded from the definition of God, it is impossible for Father and Son to differ in power.
(7) Argument: The Father cannot exist without the Son, and so cannot precede the Son in existence.
(7.1) Given the analogy with human equality, it is reasonable to define the Son as the equality of the Father, and hence as constituted qua Son by his relationship with the Father; it is also reasonable to see the Father as constituted qua Father by his relation with the Son.
(7.2) However, there is in Father and Son no possibility of distinction between essential existence, existence simpliciter, and existence qua Father and qua Son. Hence, both Father and Son are fully constituted as such by their relation.
(7.3) Given (7.1) and (7.3), and even given (6.1) it is impossible for the Father to precede the Son in any way, and especially impossible and even inconceivable that he could precede the Son in the temporal sense in which human fathers precede sons.
(7.4) Moreover, to be essentia in the sense ascribed to God is per (1) to actually exist eternally; therefore the Son actually exists eternally in the maximal possible sense; hence, the Father cannot precede him in existence.
(7) Conclusion: The Father and Son are truly distinct, possess one and the same substance, essence, and nature, are co-eternal with one another, do not differ in any way in essence, substance, nature, glory, power, or honor, and are absolutely equal and consubstantial (=ὁμοούσιος) to one another.
