Saturday, March 26, 2011

Mediaeval and Modern Logics I

Nevertheless, it is still a medieval world of thought we meet in Duns Scotus’ oeuvre, expressed with the help of scholastic tools, invented and elaborated on in Latin based semantics and logic. However, this world of thought does not depend essentially on these scholastic tools. We may pile up a list of famous names from modern logic and philosophy who have established theories Duns Scotus’ philosophy is definitely in need of: Cantor – Frege, Russell and Beth – Lewis, Kanger and Hintikka – Kripke and Plantinga – Wittgenstein, Ryle and Austin. We can also compose a list of crucial theories: the theory of sets and, in particular, the theory of infinite sets (Cantor), the theory of logical connectives and the logic of quantifiers (Frege, Beth), the logic of relation and identity (Russell, Whitehead). In general, modern standard logic is an excellent tool to translate, to extrapolate and to defend Scotian theories in combination with the ‘linguistic turn’ (Wittgenstein, Ryle, Austin). Moreover, modal logic (Lewis, Kanger, Hintikka) and the ontology of possible worlds (Kripke, Plantinga) are crucial theories to discuss adequately Duns Scotus’ ontology and philosophical and theological doctrines of God.


-Antoine Vos, The Philosophy of John Duns Scotus, 8.

I really wish that Vos made clear somewhere in his book exactly which theories by these guys Scotus' philosophy is "definitely in need of." He doesn't, so far as I recall, and so I'm left very dubious. In fact I've long suspected that set theory and its use in the foundation of modern logic has had an almost completely pernicious effect on modern philosophy, emphatically including the so-called "linguistic turn" and possible world theorizing. The common element in all of these seems to me to be a systematic conflating of the logical with the ontological order, to the detriment of the latter. When contemporary philosophy lays down at its very beginning a set of premises making it difficult if not impossible to distinguish between ens realis and ens rationis, it guarantees a failed metaphysics.

My own opinion is that, if mediaeval philosophy can take useful supplements from modern thought, these are more likely to come through the phenomenological than through the linguistic-analytical traditions. (This is what St Edith Stein tried to do, though I haven't studied her very thoroughly yet and can't say how successful she was.) One has to acknowledge, though, that philosophers today attempting to "encounter" mediaeval philosophy through the lens of either tradition are much more likely to spoil and ruin it than to enhance it.

14 comments:

Lee Faber said...

That's a rather long list of names. In what sense would it still be scotist once it had been "corrected". Plus, I hate the word "scotian".

Leo said...
This comment has been removed by the author.
Leo said...

"Moreover, modal logic (Lewis, Kanger, Hintikka) and the ontology of possible worlds (Kripke, Plantinga) are crucial theories to discuss adequately Duns Scotus’ ontology and philosophical and theological doctrines of God."

Funnily enough, I seem to recall Scotus discussing his theology perfectly well without recourse to S5. Just because you are incapable of describing modality without bringing in an infinite array "possible worlds," oh narrow-minded analytic philosopher, does not mean that nobody can. Sheesh.

Thanks, though, for the passage and insightful commentary.

Michael Sullivan said...

It's hard not to agree with you, Leo. Vos' book is valuable in a number of respects, but the writing is rather, ah, histrionic, and there are quite a number of offhand unsubstantiated statements like this.

Lukas Novak said...

This is a very interesting topic. In my opinion, contemporary philosophy is in bad need of metaphysical thought; and the best metaphysics there ever was is the scholastic one. But in my opinion if there is to be any synthesis of contemporary thought with scholasticism, it can only be with the analytic branch of the contemporary thought. Why? First, because the "continental" tradition has (leaving aside some minor exceptions like the minority realist phenomenology) rejected the very foundations on which any true metaphysics can be built. The contemporary continental tradition is still haunted by the ghost of Kant. Second, continental tradition has abandoned the only viable instrument for metaphysical enquiry, which is logic, and substitued various ersatz-methods instead, like phenomenology, or rhetoric, or poetry. Third, because the analytic tradition, not having abandoned logic, has been under its beneficiary influence for some hundred years now and so has been at least in some of its strands cured from its original antimetaphysical affect.

In my opinion there are some very useful things in modern logic and analytical philosophy, and some less so. For example, I regard the Fregean "function-theoretic" analysis of predication as philosophically deadly, the more so that it doesn't seem to be based on any arguments at all, but merely on the pragmatic consideration that it "works". But as F. Sommers has shown, term logic can work equally well. On the other hand, the apparatus of possible worlds is IMHO an excellent tool for logical analysis of modalities, and I have used it innumerable times to analyse and clarify Scotus's and other schlastics' argumentation. One only has to remember that it is just a logical apparatus, which as such is in need of interpretation as regards its "ontological import"; and the interpretation is not encoded in the logic itsef but must be supplied by genuine metaphysics (for example, a Scotistic one). In a sense, Scotus _was_ the discoverer of S5; many of his inferences that remain merely intuitively valid in his own setting, appeac crystal clear when translated into the language of possible worlds.

As regards phenomenology: I don't think that that project is flawed in itsef. It is just a method. The problem is when one starts to believe (like Heidegger) that one can distile any metaphysics from their observations of phenomena as phenomena, without "speculation", that is, logical inference from the empirical to the non-empirical. So phenomenology can be _supplemented_ with genuine metaphysics, but it cannot substitute it. Besides, the majority of phenomenologists combines phenomenological method with transcendental-idealist metaphysics. Such an amalgam is, IMHO, incompatible with any genuine metaphysics.

Michael Sullivan said...

Lukas, thanks for your very stimulating remarks. I agree with you about the continentals in general, for most of whom I have very little patience; I had in mind Husserl and Husserlians specifically. I don't think anyone could claim that Husserl abandoned logic! But I also emphatically agree with you that phenomenology has to be supplemented by metaphysics. And I have little use for Heidegger and his spawn, postmodernists, post-postmodernists, or whatever the fad is these days.

I also agree with you about Fred Sommers. I had a graduate course under him some years ago and was convinced by the validity of his approach, though I haven't followed up on it much since then. (Brandon Watson at Siris had a series of posts on using Sommers notation last year which gave a good introduction to the subject, if anyone is interested.)

On the other hand, the apparatus of possible worlds is IMHO an excellent tool for logical analysis of modalities, and I have used it innumerable times to analyse and clarify Scotus's and other schlastics' argumentation. One only has to remember that it is just a logical apparatus, which as such is in need of interpretation as regards its "ontological import"; and the interpretation is not encoded in the logic itsef but must be supplied by genuine metaphysics (for example, a Scotistic one). In a sense, Scotus _was_ the discoverer of S5; many of his inferences that remain merely intuitively valid in his own setting, appeac crystal clear when translated into the language of possible worlds.

This is very interesting and I'd appreciate hearing more about it. Do you have any examples? In my experience whenever e.g. Thomists use possible-worlds talk it comes out sounding hopelessly muddled to me.

Anonymous said...

I can understand your doubts. But what Vos is saying here, is - in my opinion - that Scotus' philosophy can be illuminated, underpinned and in some ways even be proved by contemporary logical and semantical theories.
That is, of course, quite a claim. Vos however knows what he is talking about. His Ph.D.thesis (unfortunately only available in Dutch under the title 'Kennis en noodzakelijkheid')explores these claims with the help of the semantics of possible worlds, modal logic and so on. In this book he claims that Scotus' philosophy - and especially his notion of synchronic contingency - is the key to a consistent doctrine of God.
Is that a conflation of logic and ontology? It is, but what's the problem? Take for example the law of non-contradiction. Anyone who is working in science or technology, takes this law ontologically for granted. Otherwise, you couldn't do your work. So , what is the exact problem with the conflation of logic and ontology?

Michael Sullivan said...

AT,

I don't say categorically that Vos is wrong. It's just that he doesn't elaborate in the present book, leaving the reader to guess at his meaning.

Lukáš Novák said...

I apologise that I was unable to reply earlier. Regarding Husserl - well, he started his philosophical project just like Frege, as a quest for re-achieving the objectivity of logic. But soon he came to believe that true objectivity can only be achieved on the level of pure phenomena and therefore excluded "speculation" - that is, argumentation, from his method. IMHO his mature, transcendental-idealist thought is incompatible with metaphysics - as his "objectivity" is always a subjectivised one, "objective" for him is what is _perceived_ as objective - and this is what we should swallow as the solution of the epistemological problem.

Regarding the utility of S5 in interpreting Scotus - for example, the entire line of argumentation in De primo principio toward the necessary existence of the first cause can be, IMHO, set forth very clearly by means of the possible world apparatus. It is clear, for example, that the assumed modality must be the broad logical possibility (coextensive with metaphysical possibility for Scotus), and not some "causal possibility" or so as e.g. R. Cross would like to read him. However, to argue this out properly would require much more space - perhaps I will write some paper on the topic some day... :-)

Unknown said...

I did not find any reviews of Vos and his book, other than this here. There are various comments from some. (Even some whom seem more intuitive also seem inevitably bullied back by an entrenched and fixed analytical appeal). This may provide some clarification on some of what I was feeling intuitively (early on); and it also provides perspective from an opposing side (analytical; logical; static fixed permanent metaphysical thinking). It begins, (this talk of metaphysics here), to take shape, more and more, as like unto Babylon (Genesis 11:4-9); entrenched fixed metaphysical thinking, cut off from the vine and root of original, unique, and particular thinking. I moved on early - from Vos, and his book because I believed there would be no real life found there. Yet, I came to believe there was a purpose to understand, as a pathway through along the way of a journey. On a side note, the quote that the blogger (Michael Sullivan) uses from Vos' book, is in part the same quote I use from Vos in my notes a few pages down from where we stopped last evening. It is the one in which Vos is applying all these many logical theories and more; and then making the claim that Scotus is in definite need of these. I did not question Vos as far as his belief in God. I question him upon his applied metaphysical thinking in understanding, what I believe to be, the original thinking, underlying the very heart of Duns Scotus and his contribution to philosophy. In the end, though Vos and his book on Scotus may be useful, as potential fact gathering information; I believe it will leave us empty as a means of truly gathering in, as of the heart, of this original thinkers thought. To apply all these things that Vos says Scotus is in definite need of, would be, in the end, much less than unfruitful. I looked over the ETF.edu link, looks like a great place for young people to learn... Still, I remain certain that the applied metaphysical thinking that Vos believes Scotus is in definite need of, in the end will prove unfruitful. Truly, running the risk of seeming arrogant, I stand by my original words of "much less than unfruitful". My issue pertaining to Vos, is his metaphysics, not necessarily his theology. His theology may very well likely be right, and I will not impede upon that domain, in which I have no right to impede. Yet, I will stand in or against the domain of metaphysics. One last thought, for the sake of clarity; When I said " in the end Vos and his applied metaphysic would prove much less than unfruitful", I in fact, could have included that it is Vos and his applied metaphysics - as a "means" to the end - that will prove much less than unfruitful. (1Cor 3:13-15)

Unknown said...

The condition of scholastic philosophy was that it stressed essence as primary and existence as secondary; might there have been a bewitchment by essence. Scotus was revolutionary; And in the end, most likely had been silenced due to the place his conclusions must lead. The authorities (principalities) not willing to give up their power; to give up their place to God's Holy Spirit; the radical nature of the power of transformation, upon the unique and particular individual. The principalities had a fixed solution simply by stressing static essence as truth. Yet, the Holy Spirit, and the Holy Spirit alone is the Spirit of Truth. And there is no principality that can contain in any form the essence of the Holy Spirit, whom is not fixed nor static but in motion. For the wind bloweth where it willeth.

The wind blows where it wishes, and you hear its sound, but you do not know where it comes from or where it goes. So it is with everyone who is born of the Spirit. John 3:8

Unknown said...

So where do we go from here....

Unknown said...

Come Holy Spirit, Come, may your river over flow with abundant life, Keep our eyes fixed on Jesus.

His eyes were opened, his sight was restored, and he saw everything clearly. Mark 8:25

Unknown said...

Aquinas is wrong with his analogy of analogous speech. For how else can God speak to us in words, unless the words have exactly the same meaning to Him as to us. And this applies to conversational intimacy with God as well; for how else could we hold a conversation with God; unless our words meant exactly the same thing. And in fact Aquinas; if he simply truly thought past the 'tradition' of his time and place (yet not outside of time and place); past the tradition which stressed and valued essence; while still remaining in time and place; He would see that he was contradicting the Bible and Jesus Himself; in this, by saying that the words Jesus spoke had something of a different meaning to him than they did to us. Yet, Jesus' words can speak for themselves, and in fact, can speak for Himself, and in particular, for His Father. They do not need special interpretation through analogy, nor do they mean anything different to His Father, than they do to us. They are mediated directly through the Son, and to us through the Spirit of Sonship. Jesus does not need any special interpretation by way of analogy, his Life and his work and his words were one. He does not need any essential protection of his words through placing an essential form of analogous interpretation upon them. At times Jesus did speak of the Kingdom of Heaven as likened unto... yet his words were meant to loosen our hardness of heart through our stiffness (fixed nature) of thought. His words themselves, as he is, is directly mediated unto us; and clearly he tells us He came to show us the Father, and he who has seen the Son has seen the Father. The Holy Spirit is the only mediator between God and us; the mediator of the new covenant. And He is the Spirit of Sonship, the Spirit of Truth, and among other Names, he and only he mediates to us the new covenant of Jesus Christ and to the spirits of just men made perfect, through the cross, death, and resurrection of our Lord Jesus Christ. Aquinas and others do not need to protect the essence of the Lord God through analogy; we come to direct knowledge of the Lord Jesus through his Spirit who dwells within us, and from which we cry, Father, Abba. For we..... Hebrews 12:22-29