Posted on 03/15/2005 2:41:19 PM PST by Michael_Michaelangelo
Whatever scientists call "matter" isn't what Aristotle called "matter." Aristotle's "matter" can't be further reduced.
Agreed. My point is precisely that someone who is not a 'materialist' with respect to one definition may nevertheless be one with respect to another.
The perception of color is completely beside the point. The point of a universal is that it exists, even if it cannot be perceived at all.
Would you care to shift universals with RWP and try pi or threeness?
"Our perception of color is entirely subjective."
You are recognizing this... but missing the point that "perception" is not the focus!
Did green exist before we did? Well, lets ask our good friend Photosynthesis.
Did spheres exist before man? Lets ask the planets. Just because you can't percieve a rock in the desert, doesn't mean it isn't there.
What you are trying to argue is that "We do not know what way the coin in the closed box is facing"
What we are arguing is that indeed "the coin is facing some way"
Was getting there myself, but thank you:)
The point I was first trying to drive home was that "perception" does not quanitfy existance. I have a bed behind me right now. I can't see it while I'm typing, but it's there.
And you wouldn't count the correlation between that location, and a specific range of wavelengths of light, to be objective? Sure you would -- and if you can map that location, then it would be duck soup to show that it really does respond to certain wavelengths of light.
As for the perception experiments you mentioned ... well, your description of the phenomenon shows that you've already identified how the aliasing works.
I'm pinging my favorite Freeper philosophers to the discussion as well in case y'all would care to get into the details of that discipline.
Not arguing evolution here.
Arguing perceptions.
I don't dispute that some mechanism made life on this planet more complex.
Doesn't this whole "green" problem boil down to the classic "if a tree falls in the forest and no one's around to hear it" question? In the case of the lonely tree, it certainly falls, and the air vibrates, but "sound" is a reaction in a human brain. No listener, no "sound." Or, to tie this in to the "green" question: no viewer, no green. However, I'm probably missing a bunch of subtleties, as I often do in such discussions.
If color is a behaviour of the brain, then why are people who are color blind still able to see the sky? If it is indeed simply the reaction of our brains to moving electrons, why don't coloblind people have a blank space where things with those colors are?
Our receptors are divided into spatial and light sensitive receptors. If color is objective, then shapes are as well. A blunt object would cut one person, but bounce of another. Balls only roll because we percieve them to roll.
Now does that make sense?
No, I say God created life. But of course, if God is left out of the 'equation', then one is left with life coming from lifelessness all by itself.
- Kettle Belly Baldwin in "Gulf" from Assignment in Eternity by Robert Heinlein
Not a useful test. People can identify cows, but there is no Platonic cow.
And so a fictional character represents your ideas.
Loud and clear.
Excellent post, Aquinasfan!
No, but there is an idea of "cow"
The roll of "cow" existed before you woke up this morning. You don't have to percieve it for it to be.
In general . . .
I hope you'll continue to contribute to this discussion of universals!
. . . I'll participate when I can but I probably won't be back online until at least Monday (my Internet connection on my other machine has recently become, um, suboptimal).
Here are the bare bones, for the benefit of anyone who could use a little background.
According to the standard philosophical definition, a universal is any characteristic, property, quality, or what have you, or a complex of such properties, that can occur identically in more than one context. (You may encounter the definition 'repeatable predicable', meaning a property that can be repeatedly predicated of more than one object.) If there is an identical 'man-ness' among men, then 'man-ness' is a universal; otherwise not. (I think not.) If a specific shade of green can occur identically in two different conscious experiences, it's a universal; otherwise not. (I think it is.) If the number pi can occur identically in more than one context, it's a universal; otherwise not. (I think it is.)
The problem of universals, in a nutshell, is whether there are any real universals at all, and if not, why we 'think' as though there are.
The two logical possibilites are realism (the view that there is at least one real universal) and nominalism (the view that there aren't any real universals at all).
'Nominalism' gets its name from medieval disputes over the problem, in which one view (most famously propounded by William of Ockham) was that 'universal concepts' were really just names for ranges of nonidentical objects. Today most philosophers probably wouldn't use it quite that restrictively, so we'd regard conceptualism (the view that apparent universals are really just concepts, not really-out-there objects) as a form of nominalism, not as an alternative to it.
Please note that a 'realist' is not committed to the view that anything we think is a universal really is one. For example, there may be lots of proposed universals -- I'd list 'man-ness' here -- that turn out on inspection to represent not a single identical property but a (possibly ill-defined) range of distinct properties or complexes thereof. Denying that these are universals doesn't make you a 'nominalist'; as long as you acknowledge at least one real universal, you're a 'realist'.
There are several varieties of 'realism' that I'm not going to try to sort out here. There are 'realists' who (like Aristotle) tend to think that universals don't exist 'on their own' but only 'in' particulars; these realists might also deny that universals exist in any 'eternal' or 'timeless' way. The more Platonistic ones will claim that at least some (not necessarily all) universals are self-existent and timeless. But those are subsidiary issues.
Perhaps I can give a concrete example.
It is possible to construct a set of color patches using different pigments, so that people with "normal" vision will say that two patches are identical, but people with color deficiencies will see them as different. Color blind people have been used to detect military camouflage, because they match colors differently.
Aside from monochromatic light, which can be described objectively as a wavelength, color is constructed in the eye and brain.
We can also identify herrings, red or otherwise... ;-)
Unlike the cow, you've provided an objective definition of "Platonic Green," as a specific wavelength of light. You could create and measure that wavelength without ever having to "perceive" the color of it.
There was no physical organism to hear that sound yet there you have it - proof that sound exists even if noone hears it.
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