CHAPTER 9. TROPE ONTOLOGY 126 so-called meaning postulates like
For all x it holds that if x is a bachelor than x is not married.
to the ordinary logical rules like the tertium non datur.13 Including these postulates in the semantical system sentences like
All bachelors are unmarried.
become analytic sentences. The postulation of the compresence relation may seem somewhat similar. The substratum is thrown out of the ontology since only something like the attributes, here the tropes, are needed. And then, suddenly the compresence relation is added. One could ask: is not compresence actually the same as the old substratum?
Fourth and last, one could go the opposite way and object that the in-troduction of compresence is a mere verbal trick. The question why tropes are together in a bundle is answered with recourse to the ‘being-together-relation’. There seem to be only two ways out for the trope ontologist who postulates the compresence relation. Either compresence must be given up in favour of something else or it must be explicated and justified in a convincing way.
Another question to the bundle theorist of tropes concerns the transtem-poral identity of a bundle of tropes. What ensures the identity of a bundle at two different times? This problem together with the status and explica-tion of the compresence relaexplica-tion place a heavy burden on the bundle view of tropes and are not completely settled yet for my taste.
CHAPTER 9. TROPE ONTOLOGY 127 chotomy between substance and attribute.14 Seibt argues that trope ontol-ogy soothed the ills of substance ontolontol-ogy without going down to the root of the problems which she considers to be the basic role of particulars. While Seibt sees no hope for trope ontology the reaction of some trope ontologists could be put as acting according to the motto ’attack is the best means of defense’. C. B. Martin Martin (1980) as well as, more recently, Peter Simons Simons (1994) explicitly retained a substratum-attribute view in surprising divergence from the classical stance of trope ontologists which is usually in direct opposition to that of substratum theorists.15 Simons’
conception of objects is a combination of the bundle theory of tropes and the classical split-up into substratum and attributes. According to his view objects consist generally of two bundles of tropes although various devia-tions are allowed. One bundle comprises the essential tropes and serves as a substitute for the substratum. The other bundle includes the non-essential tropes. Details of Simons’ account will be given later.
14In Seibt (2000), paragraph 4, Seibt argues that trope ontology fails to give satisfac-tory answers tothe three basic ontological problems, i. e. the problem of individuality, the problem of universals and the problem of persistence. Note, however, that Seibt does not consider these problems to be specific for trope ontology. According to her view, all ontological concepts fail in the face of these problems as long as they adhere to the so-called “substance-ontological paradigm”. It has to be stressed that the range of this paradigm is extremely wide in Seibt’s assessment.
15In effect, a substratum-attribute version of trope ontology can already be found in the philosophy of John Locke as Martin and Armstrong have pointed out. Some details of this assertion can be found e. g. in Armstrong (1989), p. 63f. Note that Armstrong uses the term “substance-attribute view” for exactly the same theory (or theories) which I call “substratum-attribute version”. The difference stems from my usage of ‘substances’
as ‘independent concrete particulars’ (see glossary).
Part V
Proposal for a New Ontology of QFT
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Chapter 10
Dispositional Trope Ontology
10.1 Introduction
The last section of part IV dealt with trope ontology in general without fundamental reference to physics. As in the case of process ontology it is primarily for philosophical reasons that trope ontology has been established and it is mostly discussed in this context. In this chapter I wish to propose a trope-ontological account of QFT building on this philosophical foundation.
My starting point will be an elaboration on an argument by trope ontologist P. Simons. He argued Simons (1994) that his “nuclear theory of tropes”
can be used for the solution of a conceptual problem in quantum mechanics, namely the problem of the individuality of ‘identical particles’.
My own proposal differs from and goes beyond Simons’ ideas in a num-ber of aspects. Simons’ trope ontological attitude has arisen out of philo-sophical considerations (at least I suppose so) and, in the last decade or so, he has been checking the applicability and appropriateness of his ap-proach in various special sciences, with physics being one among them. I am proceeding just the other way round. I start from a particular theory of one particular science, namely QFT, which - as I have argued in part II - I consider to be ontologically more fundamental than any other theory of natural sciences. In a second step I am looking for an ontological construal of nature which best fits this theory (i. e. QFT). So one can say that
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CHAPTER 10. DISPOSITIONAL TROPE ONTOLOGY 130 whereas Simons starts off being biased philosophically but neutral regard-ing sregard-ingle sciences, I start off beregard-ing biased regardregard-ing the priority of sregard-ingle sciences and neutral with respect to ontological conceptions. Of course Simons and my biases have their respective basis.
I go beyond Simons in two further aspects. First, I try to be more ex-plicit in specifying which are the fundamental tropes in the case of quantum physics. Second, my aim is to give this specification with respect to QFT and not QM as Simons does.
I briefly recapitulize the main ideas of trope ontology. I introduced trope ontology as a diplomatic way to handle the ‘problem of universals’
which mediates between extreme nominalism and extreme realism about the ontological status of properties. The treatment of properties is the salient feature of trope ontology. Properties are acknowledged as entities which really exist outside of our mind and which are not merely mental constructions or even just words. In this sense trope ontology deviates from classical or extreme nominalism and makes a concession to realism about universals by accepting the reality of properties. However, the trope ontologist still shares a (if notthe) basic scepticism of the nominalist aginst realism about universals. Both classical nominalists and trope ontologists deny that properties are universals. The trope ontologist keeps the nomi-nalistic attitude that it is inconceivable that properties are entities which exist outside of space and time and which can be multiply exemplified or instantiated. Both classical nominalist and trope ontologist think that all there is are concrete particulars, i. e. entities which occur only once (particulars) and which are at least in time and often in space as well (concrete).
Neverthess, as I indicated there is point where the trope ontologist diverts from the classical nominalist. The trope ontologist counts proper-ties as concrete particulars as well. Note however, that while tropes have concreteness and particularity in common with everyday objects like this keybord, they differ from them in that their existence is strongly depen-dent on the existence of other entities, namely of other tropes. Other more common examples for strongly dependent entities are boundaries or states
CHAPTER 10. DISPOSITIONAL TROPE ONTOLOGY 131 since they are necessarily the boundaries or the states of something. Gen-erally, tropes cannot exist by themselves but can only occur in clusters of tropes. A cluster of tropes which makes up an independently existing object is called a bundle. The tropes of a bundle are related to one another in a certain way called compresence relation.