Metaphysics Seminar 7: Ontology (4) Henry Taylor

Recap We have been trying to build an ontology, and we’ve been looking at the nature of properties. We started off with the problem of resemblance: how is it that two things are alike? We ended up with a range of options on the table.

Positions: realism and nominalism Universal realists: Armstrong, Moreland. Nominalists: Ostrich nominalism (Quine and Devitt)

Universals We then looked at what happens if you accept universals. Are they concrete or abstract? Concrete: Armstrong. Abstract: J. P. Moreland.

Universals Are universals all there are? Yes: A bundle theory of universals. No: Armstrong. There are thin particulars as well.

States of affairs We ended up with states of affairs: properties are concrete universals, that are wholly present at each instance. They are instantiated by particulars: things which have universals. Today we will be wrapping up ontology with one more view.

Tropes Tropes are properties of objects (like universals). But they are not ‘wholly present’ at each instance. Each trope is a particular. This means that each instance of a trope is non-identical with each other instance of the same ‘kind’ of trope. Each trope is distinct from each other trope.

Back to the apples. Universalist says: These two apples each instantiate REDNESS, and the REDNESS of apple 1 is identical with the redness of apple 2. Trope theorist says: These two apples each instantiate a property. Apple 1 instantiates REDNESS1, and apple 2 instantiates REDNESS2. These two REDNESS tropes are not identical: each is different from the other.

Tropes But how does this explain resemblance between objects? The universalist explanation is clear: The two apples each instantiate REDNESS. The redness of one is identical to the redness of the other. Everything resembles itself. So that’s resemblance: explained in terms of identity. Trope folk clearly can’t embrace that, because they don’t think tropes are identical.

Tropes How they do it: exact similarity. So, REDNESS1 is not identical to REDNESS2. But they are exactly similar to one another: they are non-identical but exactly alike. So REDNESS1 and REDNESS2 are exactly similar, and in virtue of this exact similarity, the two apples resemble each other.

Tropes Think of it like this: ‘Bill and Ben have the same car’ is ambiguous. It could mean that Bill has one car, and Ben another car: and each one is a red ford focus. Or it could mean that there is one car, and Bill and Ben take turns driving it. The first one is the trope theory (different but exactly similar) The second is universalist theory (identity, in the philosopher’s sense).

Questions/comments?

Tropes and exact similarity. So, each trope has some buddies that are exactly similar to it. REDNESS1, REDNESS2, REDNESS3 etc. all bound by the relation of exact similarity. These all form a set of exactly resembling tropes. Any object instantiating any trope in the set resembles all of the objects that instantiate any other trope in the same set. So, what universalists do with one universal, trope theorists do with sets of exactly resembling tropes.

Exact similarity The exact similarity relation is primitive. So what are objects? They are bundles of tropes. So, a ball is the bundle of REDNESS1, SPHERICITY1, MASS1, etc. These are bound together by another primitive relation of compresence. So, objects are bundles of compresent tropes.

Compresence vs instantiation States of affairs folk: objects are thin particulars that instantiate universals. Trope folk: objects are bundles of tropes bound by compresence.

Terminological hell! 1) Tropes are sometimes called ‘modes’ by John Heil, C. B. Martin and E. J. Lowe. That’s the older Lockean word for them. They’re called tropes by folk like Keith Campbell and Douglas Ehring. 2) Tropes are sometimes called ‘abstract particulars’ (by Keith Campbell) but that’s not because they’re non-spatiotemporal, but because they’re abstract as in you need to concentrate on some aspect of an object in order to fix your mind on them. 3) Trope theory is sometimes called ‘nominalism’ because trope folk don’t believe in universals. But they do believe in properties.

Questions/comments?

Why believe this? Bundle theories Well, look at the bundle theory of universals. That got in trouble because it had to say that two objects with the same universals were identical. This is because all the universals in both bundles were identical, and the identity of the bundle was determined the identity of the universals in it. Trope theory doesn’t have to say this, because each trope is a particular, so the two bundles have non-identical properties. So the two bundles are not identical.

Why believe this? Thin particulars Also, remember that Armstrong needed thin particulars, and these are mysterious. He needed these to explain how each object can be a particular (universals can’t do this). The trope folk don’t need thin particulars: the tropes themselves show how objects can be particulars (because the tropes are themselves particulars).

Bundle theories You don’t have to be a bundle theorist if you’re a trope theorist. John Heil and C. B. Martin are good examples: they accept tropes and substances (they call tropes ‘modes’). But it’s an advantage of trope theory that you can be a bundle theorist if you like.

Why believe this? Whole presence Also, remember the problems we had with saying that a universal is ’wholly present’ at each of its instances. Trope theorists don’t believe this, so they dodge these issues straight away.

Two problems for trope theory: 1 The big advantage of universalism is that it can explain why two objects resemble each other: because they share universals that are identical. Trope theory can do this too, in a sense: it says that two objects resemble each other if each has a trope, and each trope exactly resembles the one the other object has. But the theory can’t explain what makes each trope exactly resemble the other. Universalists explain this in terms of identity: trope people leave it totally unexplained.

Two problems for trope theory: 2 1) Suppose apple 1 has REDNESS1, and apple 2 has REDNESS2. 2) It is possible for REDNESS1 to ‘switch’ with REDNESS2 so that REDNESS2 is had by apple 1 and REDNESS1 is had by apple 2 (by the combinatoral principle of possibility). 3) The trope theorist says that the world has now changed. 4) But the supposed difference is: undetectable and makes no difference to the causal structure of the world. 5) In order for something to be real, it must make a difference to the causal powers of something (Eleatic principle). 6) (Therefore) this change is not real. 7) (Therefore) the theory that predicts it is real should be rejected (this means trope theory).

Discussion What points is Campbell making when he discusses rainbows and Cheshire cat grins? Campbell thinks that tropes are useful for: causation, perception, concrete individuals, the problem of universals, space and change. Do you agree with him about all of these? What are his arguments? What do you think of the ‘trope swapping’ argument and the argument to show that tropes aren’t explanatory?

5 positions. We now have lots of positions on the table: 1) Ostrich nominalism 2) Universal bundle theory (concrete) 3) Universal bundle theory (abstract) 4) States of affairs (concrete) 5) States of affairs (abstract) 6) Trope bundle theory Let’s do a poll.

Final thoughts: parsimony. Over the course of these lectures, philosophers have often been really worried about parsimony. The need to postulate as few entities as possible. That’s one of the main attractions of nominalism over realism. AND bundle theories over states of affairs. AND, concrete theories over concrete-and-abstract.

Parsimony More extreme example: E. J. Lowe’s Aristotelian ontology. He has four categories: 1) Modes: particular properties, tropes. 2) Universals: the universals of which a trope is an instance. 3) Individual substances: Objects. 4) Kinds: The ‘sorts’ that particular objects fall into.

Parsimony Take a tomato: The tomato is an object instantiating a mode or trope: a particular redness, and that mode falls within the property universal ‘redness in general’. The particular tomato also falls within the kind ‘tomato’. He even thinks that universals and kinds are abstract so he has concrete and abstract stuff in there!

Parsimony Each of these categories does something in his ontology (they’re not postulated for the hell of it) But clearly he doesn’t lie awake at night worrying about parsimony. What do we think of this approach?

Discussion: Final thoughts You now have the basic resources to build an ontology: Universals Particulars Abstract/Concrete Tropes Thin/Thick Particulars These are what you need to do ontology, and you will find them being useful elsewhere in metaphysics.

Next time Next week we’re leaving ontology, and moving on to modality. However, as we will see, there are lots of connections between modality and ontology, so keep your eyes peeled.