My question is simple: What is ens commune?
I believe that the/a key to understanding this idea lies in the text quoted from St. Thomas' Prooemium below. I will offer some initial thoughts and comments about the text below. I invite... no, rather I ask and urge you all to please add your thoughts to this discussion. This is for two reasons: First, I believe such a discussion is important and necessary for all those who would pursue wisdom. Secondly, and consequently, because I want to understand this and your help is needed and asked for.
Haec autem triplex consideratio, non diversis, sed uni scientiae attribui debet. Nam praedictae substantiae separatae sunt universales et primae causae essendi. Eiusdem autem scientiae est considerare causas proprias alicuius generis et genus ipsum: sicut naturalis considerat principia corporis naturalis. Unde oportet quod ad eamdem scientiam pertineat considerare substantias separatas, et ens commune, quod est genus, cuius sunt praedictae substantiae communes et universales causae. Ex quo apparet, quod quamvis ista scientia praedicta tria consideret, non tamen considerat quodlibet eorum ut subiectum, sed ipsum solum ens commune. Hoc enim est subiectum in scientia, cuius causas et passiones quaerimus, non autem ipsae causae alicuius generis quaesiti. Nam cognitio causarum alicuius generis, est finis ad quem consideratio scientiae pertingit. Quamvis autem subiectum huius scientiae sit ens commune, dicitur tamen tota de his quae sunt separata a materia secundum esse et rationem. Quia secundum esse et rationem separari dicuntur, non solum illa quae nunquam in materia esse possunt, sicut Deus et intellectuales substantiae, sed etiam illa quae possunt sine materia esse, sicut ens commune. Hoc tamen non contingeret, si a materia secundum esse dependerent.
St. Thomas mentions ens commune together with, but distinct from, separated substances. Both are considered under the formality of universal cause. Ens commune as a genus. He later goes on to name ens commune as the proper subject of metaphysics. He goes on to make a further distinction between ens commune and separated substances saying that separated substances are never in matter, while ens commune is able to be without matter.
Here are my preliminary thoughts: It seems that ens commune cannot be any really existing thing. Nor is it a fiction, but a really existing principle. It seems to be something analogous to an algebraic "abstraction" in that it is able to be understood as ens in any genus.
Some further questions that arise: Is ens commune wholly excluded from the account of separated substances? It seems clear that ens commune can in no way be said of God, but what of angels etc. ?
Further, how is it that something so ephemeral can properly be considered as the subject of a science?
Labels: metaphysics, quodlibetal question, St.Thomas Aquinas
1) Ens commune has the same extension as esse commune. (In Librum De Divinis Nominibus, c.V, l.2, n.655)
2) Angels (as all existents which receive their being) are included in esse commmune. (Ibid., n.660)
Therefore, etc.
Granted, this doesn't help much with understanding what either esse commune or ens commune means, but I thought I would throw it out there.
1) Concerning the "abstraction" question. From "De Trinitate" q. 5, a. 4, recall that, in order to determine the subject genus of divine science, St. Thomas first distinguishes between things which can be considered in themselves and as principles, and things which can be considered only as principles (form and matter, e.g.). He then distinguishes between two ways in which principles are common to a genus:
...uno modo per praedicationem, sicut hoc quod dico: forma est commune ad omnes formas, quia de qualibet praedicatur; alio modo per causalitatem, sicut dicimus solem unum numero esse principium ad omnia generabilia. Omnium autem entium sunt principia communia non solum secundum primum modum, quod appellat philosophus in XI metaphysicae omnia entia habere eadem principia secundum analogiam, sed etiam secundum modum secundum...
From this I would hold that "ens commune" falls under the first of these two headings. This seems to arise because the real "separatio" that occurs (and hence the abstraction that distinguishes the objects of metaphysics from those of physics,) requires the realization through a proof of the prime mover and his attribute of "quantity-less-ness" and hence establishes the basis of an analogical structure of predication founded upon actual knowledge of sensible being. So the mode of "abstraction" here seems to be the third mode distinguished in DT, q. 5, a. 3; hence the basis for commonality of predication in a. 4.
2) I second David's point concerning angel's inclusion under "ens commune."
3) Two thoughts occur to me concerning the ephemeral nature of "ens commune" as subject of a science.
a) It first of all seems to be dictated by the nature of the "abstraction" which establishes the definition of the object of metaphysics. This seems to be on account of our mode of knowledge. Our minds are proportioned to knowledge of material substances. Hence a "separatio" obtained through proof of an immaterial first mover ipso facto transcends our mode of knowledge insofar as it comprehends its object.
b) Having said that, I will now, of course, venture to guess at what knowledge may be above me. It seems that the angels, insofar as they have a connatural object of their own knowledge (although no abstraction), would 'experience' various degrees of "ephemerality" in their knowledges. That is to say, the closer one attains to the Divine intellect, the more real the object of metaphysics becomes.
First of all, DW I think you are right to bring up separatio. We actually just discussed this idea in metaphysics. My reasoning as follows: In order to do Metaphysics we have to do three things. First we must have a demonstration that there are separated substances. Second we must abstract from all matter and motion, even signate matter. Finally we must do separatio. This is a distinct operation from the level of abstraction necessary to do metaphysics. This separatio is what gives us ens commune.
As you can see, I depart from DW's position a bit when I make a distinction between abstraction and spearatio.
A sign that this is merited is that in DT q.5 a.1 St. Thomas says that the sciences are distinguished according to abstraction, and real abstraction, but does not mention separatio. I beleive that the separatio is another operation. I am not quite sure where one should say that this operation takes place, possibly in the 2nd act of the intellect. It does seem to be a kind of judgement.
I need to say more about separatio, but i will have to do that later. I think that it is right to turn to the division and method.
Before I head to far down this path, however, I would like to get yall's thoughts on the matter.
Vincentius and I have discussed this at length, mostly last semester. I think his further comments would be helpful here. What I would like to note first in this regard, however, is that these "operations" must not be misunderstood, and taken to be some sort of "process." They are, rather, the "level" or "degree to which," according to the nature of the intellect itself, and the nature of its object, which correspond to the level of immateriality required to define the various objects of the speculative sciences.
Consider this text of St. Thomas' from the commentary on the De Anima, I.L2, n.29:
Et notandum quod tota ratio divisionis philosophiae sumitur secundum definitionem et modum definiendi. Cuius ratio est, quia definitio est principium demonstrationis rerum, res autem definiuntur per essentialia. Unde diversae definitiones rerum diversa principia essentialia demonstrant, ex quibus una scientia differt ab alia.
In the context of this passage, however, St. Thomas has just finished making a distinction between sensible and intelligible matter (This is the portion of the De Anima where Aristotle answers whose concern this science is).
I would venture, however, that "separatio" could be fit into this schema, for St. Thomas is clear that this "operation" is required to attain the object of metaphysics.
It seems that therein lies the key to understanding to what degree "ens commune" is a certain mode of defining an object: "being" simply as such, "abstracting" or more properly "separating" from any particular considerations of matter.
Could you specify what you mean by abstracting from all matter AND performing a separation? I don't see St. Thomas mention abstraction in q.5, a.1. He speaks of abstraction broadly at the beginning of q.5, a.3, but I argue that there it is not brought up as opposed to separation. Rather, he clarifies the two in the course of the article. His final position is that in cases where the two things being distinguished can actually exist apart, separation obtains RATHER than abstraction (line 256). I suppose you could have the universal abstraction necessary to all sciences first, then make a separation proper to metaphysics, but I don't think ens commune itself is abstracted in this way. If it were, ens commune would be univocal (since abstraction is simply thinking something while not thinking something else that exists with the first).
Furthermore, isn't proving that there is a non-material being equivalent to making the judgment that being does not have to be in matter? This seems to me to be the very separation necessary to see an object beyond the grasp of physics.
So, I suppose I would collapse your three steps into one. Thoughts?
That being said, I think that it is still necessary for abstraction to precede separatio, just as physics must precede metaphysics in the order of learning. So, I am inclined to the position which you rejected at the end of you last comment V., namely there is the universal abstraction proper to the sciences and then separatio proper to metaphysics.
What is implied in what I am saying is that ens commune is a separabilia. Now St. Thomas does call ens commune a genus, doesn't that imply that it is univocal? Moreover it is the subject of the science, so ought it to be univocal?
The tricky part of what I am holding is that ens commune is in a way made up. That is it is a kind of fiction.
I finally want to say that I modified my accounts and changed the order but would still like to keep the three steps, viz. universal abstraction, demonstration, separatio.
So in answer to your last ojection, I would say that the demonstration that there is an immaterial being would incline one to make such a judgment that we can consider separables, but that in order to properly make such a judgement we have to do a careful consideration of a lot of experience. A sign of this is that Aristotle spends several books of the metaphysics (11 of them?) determining whether there can be such a science. A think part of this is caused by determining whether we can properly make such a separation.
Therefore, it is granted that we can prove the existence of an immaterial being, but it does not seem to me that it follows that we can right away see that there is a proper subject of metaphysics. We might merely be able to reason about such things insofar as they are principles of material being. There seems to be a good deal more reflection to do before we can make the judgment to separate ens commune.
I end my comment thus: ?
Thanks for your follow-up.
Regarding your questions concerning the univocity of ens commune:
1) St. Thomas does refer to being as a genus (see, for example the Fourth Way), but I think it is in a loose, non-univocal sense of genus. For he argues explicitly for the fact that ens is not a genus (following Aristotle at 998b 21-27): ST, Iª, q.3, a.5, co; SCG, Bk.I, Ch.25, n.6. Note that this argument follows from the strict univocal notion of genus, which would have to be differentiated by distinct differences. Hence I think when he does speak of being as a genus, we should take it in a looser meaning, as a (non-univocal) notional grouping.
2) See Aristotle's Metaphysics, Bk.IV, Ch.2. The money quote: "For not only in the case of things which have one common notion does the investigation belong to one science, but also in the case of things which are related to one common nature; for even these in a sense have one common notion."
I agree with you that universal abstraction would have to precede the demonstration of immaterial beings. I only wanted to head off the notion that ens commune itself was abstracted. If it were, there would be nothing left in the notion, having left aside all possible differentia. Then, we're off to Hegel-land.
I welcome your suggestion that the bare proof of an immaterial being does not immediately result in seeing the subject of Metaphysics. It seems right that there are still a lot of questions to be resolved at that point before you can start in. Maybe we can say the proof is at least necessary to prompt those questions, but not sufficient to answer them.
You helped resolve some difficulties in my mind. In particular, I was confused about why St. Thomas would call ens a genus. I had forgotten about that broader sense of genus, and hence my confusion. I actually recently read about the broader sense of genus in De Veritate. It is interesting to note the authority used to justify this broader sense of genus.
Vel dicendum, quod veritas prima quodammodo est de genere animae large accipiendo genus, secundum quod omnia intelligibilia vel incorporalia unius generis esse dicuntur, per modum quo dicitur in Act., XVII, 28: "ipsius enim Dei et nos genus sumus." (DV I,4 ad s.c. 8)
If then, ens commune is of this sort, would we say that it is an ens ratione? If it is an ens ratione then is it with or without a foundation in things?
I am inclined to say that it is an ens ratione with a foundation in things. A kind of fiction that is used in order to treat being in a common way.
Thoughts?