Sapius wrote:David : The question is, does such a conception actually refer to a reality in the physical world? Or alternatively, does our mental concept of a vacuum involve a contradiction in terms?
S: it might help if you could tell me if the ‘physical world’ is a contrived mental construct or not?
D: It is a contrived mental construct, but because we directly experience what this concept points to during each moment of the day, it differs from the vacuum-concept.
You mean points to something empirical? May be It could differ, but does
direct experience automatically make the ‘physical world’ more credible than a contriver mental construct?
It is more credible in that our experience of what we call the "physical world" cannot be refuted.
Well, I could point to the Magdeburg hemispheres experiment then.
Nothing in that experiment indicates that a perfect vacuum is created. At best, all it indicates is that a partial vacuum is created via the removal of air molecules.
Sapius wrote:In the case of a vacuum, we don't know if we ever experience it in the physical world or that it even exists.
As far as a vacuum goes, what exactly would there be to experience, except experience its effects? If direct experience is what you place your faith in, then I might have to build a big enough vacuum cleaner to fit a person.
What you say here of vacuums is true of all phenomena in the world. We only ever experience the objects of the world through their effects.
That we have experiences at all cannot be refuted. That a portion of these experiences involve what we call the "physical world" also cannot be refuted. That a few of these experiences involve a perfect vacuum cannot be determined.
Show me causality then. What exactly are you going to point to?
First, I would point to the logic of causality. Then, once you understand the logic and have allowed it to wipe away all of your delusions concerning the nature of existence, you will be able to see it in all of your experiences.
In other words, I would point to your mind which does the experiencing and urge you to clear that up.
Show me time then.
Later.
Show me gravity then. Show me electromagnetism then. (I’m sure the more learned could point to other similar things as well)
Are you talking about the observed effects of what we call "gravity" or "electromagnetism"? Or about what science currently theorizes about them?
We do define vacuum, don’t we? Same status as mathematical points you say… how do you think planes and ships navigate and reach their intended destinations if those abstractions were without a referent?
While a mathematical point has no physical referent in the sense that there can be no entity with zero dimensions existing in the physical world, it can be used loosely to represent a place or location. That is, by contradicting its own definition.
For example, we can use mathematical points to measure the distance between London and Rome, even though neither city is an entity with zero dimensions.
Sapius wrote:To put it another way, the "physical world" is a label we give to a particular set of experiences, while the "vacuum" is a label we give to something which hasn't been experienced (as far as we know) and which may never be experienced.
So that makes it the same as ‘emptiness’ then, which is logically “there”, but which may never be experienced, so what crime did ‘vacuum’ commit?
"Emptiness" is a label given to the true nature of the world, which is experienced by those who have removed all of their delusions and are able to perceive the world without any mental distortion.
By contrast, a vacuum is a possible phenomenon within the world. If it exists, its true nature would be emptiness as well, the same emptiness which comprises all things.
Further more, could there not be another reason than some 'out of logical necessity'? That being that you trust your eyes, and that direct experience of scattered things are added up as a contrived mental construct... result... totality.
Ah! You can't even actually point to totality either, which you cliam EXISTS beyond the mere concept. What exactly are you going to point to? The ALL? So how exactly does one come up with the ALL would be the question? And how exactly does one directly experience THAT?
You are going the wrong way about it if you think that perceiving the ALL involves adding things up to form a totality. Rather, it involves understanding the logic of the All, discerning how it necessarily exists, and observing how it is impossible for anything to be apart from it.
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