John West wrote:

You've said you're a materialist and suggested at a few points that something is material if and only if it's spatially qualified.

Better to say that something is material iff minimally it entails spatial qualification. So as to avoid the possible charge that one is analytically ruling out spatially unqualified material entities (e.g. an infinitely large object).

John West wrote:

What about the property or property-instance of being spatially qualified? Is it spatially qualified? You can escape the implied objection by adopting blob nominalism, but then that is another requirement of your view we need to flag.

There are no such things as properties. Or to make a more modest claim, no good reason to think that properties exist.

surroundx wrote:

There are no such things as properties. Or to make a more modest claim, no good reason to think that properties exist.

Shall I assume that you also reject property-instances (i.e. tropes in Armstrong's sense)? Or to put it another way, that you mean "properties" as opposed to substances rather than "properties" (universals) as opposed to particulars?

John West wrote:

It's worth distinguishing omnipresence and non-spatiality. If an entity is omnipresent, it exists wholly at every location and therefore isn't spatially qualified; if, however, it's non-spatial, it doesn't exist in space at all and therefore also isn't spatially qualified. I know you deny the existence of non-spatial entities, but there is still a conceptual distinction that should be flagged for the sake of conversation.

Not all omnipresent entities need be non-spatial. However, all non-spatial entities are omnipresent. So the conceptual distinction is sustained, while doubling down on their connectedness.

Personally, I would generalise omnipresent to "ranges over every ontic locus". I don't see why it is restricted to talk about physical locations, especially since the nature of space is so heavily disputed (as in the present thread). 

With ontic loci in mind, if something is non-spatial then it is either "everywhere" or "nowhere". It either ranges over all ontic loci, or none at all. Thus all non-spatial entities that exist are omnipresent. There is no middle ground between "everywhere" and "nowhere" in virtue of the fact that non-spatial entities, as non-material, lack the kinds of limitations that material entities have. Thus there isn't any limit which could restrict a non-spatial entity to a non-zero non-maximal set of ontic loci.

All non-spatial entities being simple, since composition is a physical phenomenon, cannot differ between ontic loci lest they fall foul of the Identity of Indiscernibles.

John West wrote:

It's also worth distinguishing negative reality and not existing. If space is a negative reality, it has the same status as Martin's absences, or Armstrong's limits; if, however, it doesn't exist, it simply doesn't exist. You may have used “negative reality” to mean not existing, but it's easily confused with the sense I give negative reality here.

I mean "negative reality" in the sense that you describe when I'm talking about empty space. Empty space is simply the complete absence of entities from a particular portion of reality. When talking about space in an unqualified sense it simply does not exist.

John West wrote:

Now, suppose that in possible world w particle a exists in our galaxy, and that in some other possible world v it exists in some far off galaxy. What makes it true in w that “a exists in our galaxy, but not the far off galaxy”? What makes it true in v that “a exists in the far off galaxy, but not ours”? You're welcome to reject various realist theories of truth to avoid this objection, but then that is a requirement of your view.*

*You, for example, would have to reject the plausible thesis that most truths about the exterior world are made true by entities (entities in the broadest sense) in the exterior world (i.e. "most" to avoid quibbling over the two most controversial cases, negative truths and general truths), and commit to one of a limited range of more “deflationary” accounts of truth.

I'm not sure how this is supposed to be an objection to my view/s. Nor am I sure whether you intend both a's to be numerically identical or merely qualitatively identical. If the former, I reject transworld identity, indeed I reject numerical identity altogether. It seems it would take us on a tangent, so if you could explain the relevance of the question, I'd be happy to respond in a fuller manner.

John West wrote:

Here is another argument. If space has any property, it exists. Physicists tell us space has properties (e.g. curvature, structure). Hence, we have good reason to believe space exists. I'm assuming you're a direct realist, rather than an indirect realist or idealist.

Physicists don't tell us that space has properties. Or at least, for example, talk of space-time being curved doesn't adjudicate upon the question of the ontic status of space. As Steven Weinberg has pointed out, you can dispense with the notion of curvature without any negative effects. Mathematical models do not automatically equate to ontological commitments. From the fact that a mathematical model gives you the desired results, does not mean that it is the true model.

John West wrote:

Shall I assume that you also reject property-instances (i.e. tropes in Armstrong's sense)? Or to put it another way, that you mean "properties" as opposed to substances rather than "properties" (universals) as opposed to particulars?

Properties of all kinds are mere abstractions.

surroundx wrote:

Miguel wrote:

Wouldn't that undermine reason? What is the specified geographical location of the propositional content of my thought that "Socrates is a man"? It's absurd. One way out of it would be to reject mental causation, but that's just the standard problem with materialist theories of mind being self-defeating and incompatible with reason.

Do you think that your thought literally is "Socrates is a man"? Or something else?

 
I think my thought has a propositional content which is causally relevant as a ground for other thoughts. My thought that "Socrates is a man" isn't just neurons firing, it has a propositional content (which I take to be a universal form) which plays a causal role in the conclusion "Socrates is mortal".

If there is no literal propositional content, or if there is propositional content but it is not causally relevant to my thoughts (per the causal closure of the physical), then my inferences are not valid and there is no reason, so it's self-defeating. None of my thoughts that "materialism is true" would have any causal relation to, or follow from, the actual meaning and propositional content of what I take to be evidence for the conclusion. My thought that "Socrates is mortal" was literally just caused by salts and electricity and not by virtue of the propositional content of previous thoughts about Socrates, which should serve as a logical ground for the conclusion. It's invalid.

But if propositional content is causally relevant (mental causation) then specified geographical location cannot be a requisite of causation.

Last edited by Miguel (3/20/2018 11:17 am)