Non-Substantial Change, Trope Bundle Theory, and States of Affairs

I am presently writing a review article for Metaphysica about Bo R. Meinertsen's Metaphysics of States of Affairs: Truthmaking, Universals, and a Farewell to Bradley's Regress (Springer 2018). Since I will probably incorporate the following critical remarks into my review, I want to give Bo a chance to respond. 

Substantial and Non-Substantial Change

One way a thing can change is by coming into being or passing away. This is called substantial change.  We could also call it existential change. The other way could be called alterational change. This occurs when a thing, persisting for a time, alters in respect of its intrinsic properties during that time.  Consider the ripening of a tomato. This typically involves the tomato's going from green to red.  This change in respect of color is an alterational, or accidental, or non-substantial change. One and the same entity (substance) persists through a non-zero interval of time and instantiates different properties (accidents) at different times.  As I would put it, there is no alterational change without existential unchange: numerically the same tomato is green, hard, inedible, etc. at time t and red, soft, and edible at later time t*. Bo and I are both assuming that things in time persist by enduring, not by perduring. 

The Problem of Non-Substantial Change of Continuants

This is 

. . . the problem of how to ground the fact that continuants 'persist through change'. For instance, a tomato's changing from red to green [sic] is a case of non-substantial change, and how do we ground the fact that the tomato that has changed exists both before and after the change? The bundles of basic trope theory essentially have the members they actually have and are therefore incompatible with such change. (Meinertsen 2018, 49)

The problem is that we want to say that one and the same tomato goes from being green to being red. We want to be able to uphold the diachronic identity of the tomato as it alters property-wise.  But this is impossible on basic bundle-theoretic trope theory because trope bundles have their members essentially.  This means that if bundle B has trope t as a member, then it is impossible that B exist without having t as a member. The counterintuitive upshot is that a green tomato assayed as a bundle of tropes ceases to exist when it ceases to be green.  This implies that our tomato when so assayed cannot undergo alterational, or accidental, or non-substantial change when it goes from green to red, hard to soft, etc.  It implies that every change is a substantial change. I agree with Meinertsen that this is a powerful objection to the basic bundle-of-tropes assay of ordinary particulars.

Does a State of Affairs Ontology Face the Same Problem?

Meinertsen says that it does not:

State of affairs ontology has no problem in dealing with the problem of non-substantial change. None of the properties of a particular in a state of affairs — which as we shall see in Chap. 5 is a bare particular — is included in it, as opposed to instantiated by it. Hence, it changes non-substantially if and only it ceases to instantiate at least one of these properties or whenever it instantiates a new property. (49)

It seems to me, though, that states of affairs (STOA) ontology faces, if not the very same problem, then a closely related one.

Critique

It is true that a bare particular does not include its properties: the bare or thin particular stands to its properties in the asymmetrical external relation of instantiation.  So what Meinertsen is telling us is that it is the bare particular that remains numerically the same over time while some of its properties are replaced by others. This is what grounds the diachronic numerical identity of the continuant.  The substratum of change is the bare particular 'in' the tomato, not the tomato as a whole.

But this answer is less than satisfactory. What changes over time is not a thin particular, but a thick particular. It is the green tomato with all its properties that loses one or more of them and becomes a red tomato.  This is supported by the fact that we do not see or otherwise perceive the thin particular; we do, however, see and otherwise perceive thick particulars.  What we have before us is a tomato that we see to be green and feel to be  hard, etc.,  and that we then later see to be red and feel  to be soft, etc.  

Arguably, then, it is the thick particular that is the substratum of non-substantial change, not the thin particular. If so, then a problem arises similar to the problem that arose for the bundle-of-tropes theory. How?

Well, the green tomato is a STOA whose nature is N1, where N1 is a conjunctive property the conjuncts of which are all the intrinsic properties of the green tomato. The red tomato is a STOA whose nature is N2, where N2 is a conjunctive property the conjuncts of which are all the intrinsic properties of the red tomato.  These STOAs differ numerically for they differ in one or more constituents.  The first has greenness as a constituent, the second does not. A STOA is a complex, and two complexes are the same iff they have all the same constituents. 

So what's the problem? The problem is that any non-substantial change in the green tomato assayed as a STOA destroys its identity just as surely as any non-substantial change in the green tomato assayed as a bundle of tropes destroys its identity. On either account, there is no adequate explanation of non-substantial change. This is because there is no numerically self-same substratum of change that endures through the change in properties. The thin particular is not plausibly regarded as the substratum. I note en passant that Gustav Bergmann regarded bare particulars as momentary entities, not as persisting entities.

The problem set forth as an aporetic sextad:

1. There is no change in intrinsic properties of an ordinary particular over time without a numerically self-same substratum of change. (endurantist assumption)
2. The green tomato changes to red. (pre-theoretical datum)
3. The green tomato that changes to red is a thick particular. (pre-theoretical datum)
4. Thick particulars are STOAs. (theoretical claim)
5. STOAs are complexes. (true by definition)
6. Two complexes are the same iff they share all constituents. (theoretical claim)

These six propositions are collectively inconsistent. My question to Meinertsen: which of these propositions will you reject? Presumably, he will have to reject (3) and say that 'the green tomato' refers to an invisible thin particular, and it is this item that changes from green to red and that serves as the substratum of change.

What do I say?  For now I say merely that, pace Bo, on the issue before us, STOA ontology is no better than the bundle-of-tropes theory.