John West wrote:

Spatial relations are extrinsic properties. I think, however, that what's needed to block the case of the two minds is an Identity of Indiscernibles restricted to intrinsic properties. (We can't appeal to spatial relations with non-spatial minds.) The rock argument does seem to be a counterexample to an Identity of Indiscernibles restricted to intrinsic properties.

I'm not sure I'd agree that spatial properties are extrinsic per se. A physical object can only exist in a physical space, and there must be something else in that physical space other than the physical object, and hence that physical object must exist in a spatial relation to whatever else is in that space. I cannot conceive of a rock existing by itself, without a physical universe containing other physical stuff for that rock to exist in, hence that rock necessarily participates in spatial relations with whatever else it is present along with. So, particular spatial properties might not be intrinsic to the rock, but being a participant in spatial relations with distinct entities is. In terms of visual phenomena, one cannot just see a rock by itself, there must always be something else in one's visual field besides the rock, and the rock must exist in a spatial relation to whatever else fills one's visual field. (If the rock is very large, and one is standing very close to it, it might fill one's visual field; but, as one moves one's field of vision, one would see an edge, and hence a spatial relation with something other than the rock.) The very act of observation presumes a spatial relation between observer and observed; we cannot observe anything without being in some spatial relation to what we are observing. (I would say, that while minds don't inherently participate in spatial relations, their perspectives, their vantage points, do; and public experience presumes a public space in which one has a particular location.)

Well, given that our visual experiences are just constructions out of sense impressions (themselves grounded in our minds), I think it's odd that there are blind men.

If there exist n distinct types of qualia, why should it be odd that some minds might not contain all those distinct types of qualia? Maybe some minds only contain n-1 or n-2 or n-3 of those distinct types of qualia. Maybe there are non-human minds (animal minds, extraterrestrial minds, angelic or demonic minds, the divine mind) with types of qualia absent from every human mind? We know some animals have additional senses missing in humans, for example electroreception (ability to sense electrical fields); assuming those animals have conscious minds, it would follow those minds have electroreceptive qualia entirely absent from human minds. It is not inconceivable, that through advances in genetic engineering, we could one day create human beings with this additional sense, and then there would be human minds with that type of qualia too. Maybe God or the angels have types of qualia we cannot even begin to imagine.

I also think this response just pushes the problem back a step. For example, it's plausible that there are deaf, blind men—some war veterans, perhaps. If there are deaf, blind men, the problem reoccurs. (I have no doubt that you can come up with some phenomenalist explanation of why there are deaf, blind men. I think, however, that any such explanation is going to be more contrived, and possibly ambiguous, than the corresponding direct realist explanation.)

I doubt there is anyone, no matter how profound their sensory impairments, who is totally deprived of spatial sensory information. Even if someone is deaf, blind and quadriplegic, they almost certainly still have some tactile sensations somewhere on their body, and those tactile sensations will have a spatial component – if you touch them on their head, they will know where on their head you are touching, and if you move your fingers up and down their face, they will know when you are moving up and when you are moving down, etc.

You mention war veterans; a person whose sensory impairments are a result of injury is maybe not the best case to consider. If a person is suddenly rendered blind, they might not ever again (in this life) have visual experiences, but they still may have visual memories; they can use those visual memories in constructing and maintaining their concept of space. I think your line of argument works better if you limit to people who have had that impairment since birth or infancy.

Hi Incessable,

No worries about verbosity. The point of these discussions is to get at the truth. If doing so takes a few more words, that's fine by me. (D. C. Williams once called metaphysics: “The lowest and grubbiest inquiry round the roots of things”.)

One problem with executing this standard is that there is a lack of clear definition of what is an "independent principle", so you might count more or less independent principles in a theory than I do.

Principles are independent when they're not derived from any prior principles. They are therefore sometimes not very well justified—nothing precedes them to justify them[1]. As one unpacks their implications, they can also lead to conflicts in one's theory. So, Williams's point is that one ought to start from the smallest number of principles not derived from any prior principles.

I would say that the principle of parsimony requires us, ceteris paribus, to prefer theory A to theory B when theory A is significantly simpler than theory B; it does not apply if theory A is only ever so slightly simpler than theory B. A few thousand atoms less might be ever so slightly simpler, but it is certainly not significantly simpler. A googol (10^100) atoms less would be very significantly simpler.

Dennis got this one in his first paragraph.


[1]Ideally, I try to base independent principles on the corpus of uncontroversial Moorean truths, with some further support by retorsive arguments where possible.

It's worth drawing the distinction between determinables and determinates. Mass is a determinable universal; being 0.444 kg in mass is a determinate universal. Shape is a determinable; being a specific isosceles triangle is a determinate. Having a spatial relation with another object is a determinable; having a spatial relation of 3.055 metres with another object is a determinate:

I'm not sure I'd agree that spatial properties are extrinsic per se. A physical object can only exist in a physical space, and there must be something else in that physical space other than the physical object, and hence that physical object must exist in a spatial relation to whatever else is in that space.

Suppose there are determinable universals. Further suppose that there are two apples: one a specific shade of crimson and the other, a specific scarlet. Believers in determinables claim that both apples instantiate the universal red.

But each universal is strictly identical in all its instances[1], and the specific shades of crimson and scarlet aren't strictly identical. So, since the shades can't be both strictly identical and not strictly identical, there are no determinable universals. (The argument can be rerun with properties like shape and length—that lengths are sometimes partially identical doesn't affect the argument.)

Mutatis mutandis determinable spatial relations.

One reply is to say that determinable properties like colour and red are second-order properties of the determinate red properties. So, the specific crimson and scarlet are identical in their redness.

But these second-order determinables aren't doing any causal work in our ontologies. (What causal work there is to do is being done by the completely specific properties like crimson and scarlet). So, by the principle that causality is the mark of being, the second-order determinable properties don't exist.

For the similar reasons, there are also good parsimony-based arguments for excluding determinables.[2][3] If there are no determinables, the spatial relations between the rocks can be different determinate spatial relations in different worlds. Hence, no specific spatial relation is an intrinsic property of the rocks. Hence, spatial relations are extrinsic properties of the rocks.

But suppose you could admit second-order determinables anyway. Then the rocks would each have one of the identical determinables for every determinate spatial relation they have, and one determinate spatial relation for every other spatial entity in the universe. Since there would be an equal number of these other spatial entities for each rock, the rocks would be identical in respect of those second-order determinables. Since the rocks would be identical in respect of the second-order determinables, they would still succeed as a counterexample to an Identity of Indiscernables restricted to intrinsic properties. (Mutatis mutandis first-order determinables.)

I cannot conceive of a rock existing by itself, without a physical universe containing other physical stuff for that rock to exist in, hence that rock necessarily participates in spatial relations with whatever else it is present along with.

The standard form of conceivability arguments is: x is conceivable. Everything metaphysically impossible is inconceivable (ie. Euclidean square-circles are inconceivable). Hence, x is metaphysically possible.

Unlike conceivability, inconceivability isn't a guide to metaphysical possibility. It's unlikely you can conceive of certain highly complex geometric shapes, or subatomic particles, or God, but they're all possible. So, there's no reason to take your inability to conceive of a rock-only world as reason think a rock-only world impossible.

The suggestion that God can create two rocks but not one, or a rock and a horse but not just the rock, is also incredible. There's nothing logically impossible or against God's Nature about God creating a world with just a rock. God can do everything not logically impossible or against His Nature. Hence, God can create a world with just a rock. If God can create a world with just a rock, it's possible for a rock to exist without any spatial relations. Hence, spatial relations are extrinsic properties of the rocks.

On a more general note, I know you're just defending the Identity of Indiscernibles restricted to intrinsic properties, but I still think the appeal to spatial relations (intrinsic or not) misses the mark. You've already allowed that the rocks can be “otherwise identical”, and non-spatial minds can't have spatial relations[4].


[1]This just follows from what universals are.
[2]So, “red” isn't a property. Completely specific reds are. Red is a meaningful predicate that applies in virtue of the completely specific shades of red.
[3]To avoid begging the question, I've appealed to your formulation of the parsimony principle.
[4] “Either he creates two (otherwise identical) rocks with distinct locations, or one rock with single location.” (#7)

Hey Tim,

But isn't the redness causing the properties to be either crimson or scarlet? Might this be really analogous to degrees of heat properly so-called (i.e. 'degrees of heat' answers the question "How hot?")? I mean presumably neither 'warm' nor 'hot' is understandable absent 'heat'. So wouldn't crimson or scarlet be really more like 'second-order' beings in that respect? I mean, to be sure, priority for any determinate seems to rest on the determinable. Now if determinates cannot be absent the determinable, then determinables would seem to enjoy a causal superiority or, again, at least priority: remove redness and there could be no crimson or scarlet.

Well, the statement would have to be: “If determinables exist, then determinates are ontologically dependent on determinables.”[1]

It's worth introducing the notion of supervenience. An entity, Q, supervenes upon entity P if and only if it's impossible that P should exist and Q not exist, where P is possible.

Red supervenes on crimson, and red supervenes on scarlet. Crimson and scarlet don't, however, supervene on the red. The red could be instantiated on maroon instead. So, I think it's true that if determinables exist, determinates are ontologically dependent on determinables.

Now all you need is the premise: “Determinables exist.” Whether determinables exist is, however, precisely what's at issue in that section of my reply. (I actually think the ontological dependence statement generates a further argument against determinables. It's a shade of red; intuitively, it's not red because of something extra on top of it.)

It might have been better had I put the causality argument in terms of a primary property instead. For instance, the property of being 0.333 kg in mass seems to be what's doing the work, not"mass".


[1]If P ontologically depends on Q, then it is impossible for P to exist without Q existing.
[2]The definition is thanks to D. M. Armstrong.

Last edited by John West (3/07/2016 3:42 pm)

John's fine, Tim:

However, I think the premise that determinables exist is not so difficult to establish. Crimson <I>is</I> a color and <I>is</a> a shade of red. And if it is true that every shade of red is red, then crimson is also red. But then why is crimson said to be a shade <I>of</I> red?

Well, I think the statements “Every shade of red is red”, and “Crimson is red” are true. I don't, however, think that predicates stand in one-to-one relations with properties.

First, I don't think that properties stand in one-to-one relations with predicates. For instance, there are almost certainly properties for which human language has no terms. Hence, these properties can't stand in one-to-one relations with predicates.

Going the other way. I don't think that predicates stand in one-to-one relations with properties. If, for instance, every disposition predicate stands in a one-to-one relation with a disposition, we can quickly generate an infinity of dispositions of a being by replacing the dash in "is disposed to—":

is disposed to dissolve
is disposed to dissolve when placed in water
is disposed to dissolve when placed in water on Sundays or Mondays,
is disposed to dissolve when placed in water and is such that snow is white,
etc.

In Molnar's words, word-making is not world-making. So, I would say that statements like “Every shade of red is red” and “Crimson is red” are true in virtue of the totality of (things that are) shades of red, but that there are only specific shades of red among the furniture of the world.

This is a standard position among contemporary metaphysicians, including the powers theorists. One cool result is that the problem of attributes turns out to have been based on a simple mistake of conflating predicates with properties. This, I think, is part of what Aquinas was getting at when he applied the doctrine of analogy to it.