The question is in the title: can we say that a filled hole is still a hole?
For example, can we consider that a hole dug in dirt and filled with sand is still a hole?
My opinion on this is that if a hole is filled with a different material, it is still a hole. Do you have any documentation that refers to this issue?
It depends upon you definition of "hole". Like your definition of a hole (deduced from your question statement) is:
It also depends on how much the container's material is different than the filled material (Highly subjective).
For example, More people will call a hole filled with snakes and snake-lings a hole than the people calling a hole filled with sand a hole.
It also depends upon context of the statment.For example,
It is all up to you to decide, IF you are asking philosophically, otherwise there must be clear definitions for a hole exist, linguistically (that would be out of this forum's scope, I guess).
A hole, by definition is a gap, or cavity. A filled hole is simply what it's called: a cavity that no longer exists. So, a filled hole is not a hole.
Holes are a negative in the first place: A not being within a certain being. It is a notion of difference.
Take a hole in the street, for example: Even if it is filled, it can be perceived as a hole in the street because the filling is not the same, no unity, with the street. But it does not have to be perceived as a hole anymore.
It is a matter of conceptualization: If I perceive the street as a plain unity, despite of filled holes, it is a street without holes. If I perceive the difference of the filling to its environment, I perceive it as a hole in the street, although it remains the very same street. But it does not exclude each other, otherwise we could not perceive a "street with holes". But without perceiving the differences as difference, there will be no holes.
And this is not the only problem within this: If my concept of a street is that of a flawless plain, because I never saw damaged streets, every difference will seem to be a "hole" for me (I take fractures out of consideration at this point). If I am used to see repaired streets all the time, only if it is not repaired (i.e. filled with proper stuff that a cars can roll over without a difference) it will be a hole for me. An asphalt street repaired with pebble and sand will be a street with a filled hole, whereas if it is repaired with bitumen it will be a repaired street without holes for me.
TL;DR: The more difference (from my concept), the harder it becomes to perceive a unity without this difference, therefore it becomes "natural" to see holes rather than "flawless" unity.
This, of course, pushes me away from any naturalistic epistomology or form of realism (Plato,Locke,Berkeley,Price, Russel, Searle). But that's okay for me, because I stick to transcendental idealism/constructivism (Kant, Sellars).
A hole was named a hole because it was empty of visible and tangible stuff. So how can it still be a hole once it is filled with visible and tangible stuff?!
But I would like to use the question as a beautiful metaphor that describes how we do not experience reality as it is; dynamic and undefined except by some convention for the purpose of communication. Language with its use of fixed words has conditioned our minds to think of things as persisting in time, as though they have essences that are more or less permanent and are encapsulated in the words referring to them. A classic example which is very close at home is our thinking that we are the same entity that was a child 50 years ago and a young person 30 years back; in a sense we still call a hole that was filled, and no longer a hole, a hole!
It is a good pointer for awakening someone in order to bring him/her to the present moment by saying to him; " Wake up! You are still thinking of the filled hole as a hole!"
A hole is a gap of material or object.
Many people believe if you fill up hole with a solid, then it does not remain a hole. However if you fill it with liquid, it does remain a hole. They say this because you can go through a liquid, and not a solid. But this is all simply based off of human perception. If you believe that if a hole is filled by a solid than it is no longer a hole, then you are simply only thinking in a human geared manner. There are organisms that can go through certain solids, so to them is the hole not filled?
On the contrary if you say "No it is not a hole when filled with a liquid" then you imply that filling a hole with any form or state of matter makes it not a hole. But if this is true, then there is always air in a hole, which means holes simply do not exist, unless there is a vacuum of some sort. Therefore the hole is always filled.
A hole by definition needs to be filled by a foreign matter. It is simply a gap in the plane of a construct of matter filled by a conjoining foreign matter. For example a scratch does not conjoin its points do not meet. If the break is complete but does not conjoin it is a split of fracture. Black holes are matter in void. Voids with matter are terrestrial objects. All holes are by definition filled. For example a hole in a wall is filled by air. If there was no air (vacuum) it would be a void in a wall. For a void to exist in a piece of matter than we are common with would supersede the common use of physics in definition of a hole.
I'd argue that a "hole" is only properly defined as a description of an object said to have a hole.
Thus, a hole is removed via filling insofar as the stuff that fills the hole is considered to be part of the object you're considering.
This is consistent with intuitive usage:
Filling a glass cup with glass until it is a glassy cylinder removes the hole, but filling it with air does not, because the air is sufficiently different from the glass. Liquid water is somewhere between glass and air in its closeness to the cup, which is why it makes sense to dispute if the hole is still there.
The same goes for holes in the ground, and for every other kind of physical 'hole' I can think of.
Holes (as the word is commonly understood) are almost always filled with something else, so a filled hole can, in at least some cases, still be considered a hole. The most obvious example is a hole dug in the ground. It is filled to the brim with air (which are particles with mass just the same as filling it with sand would be). In many cases, it is also filled with electromagnetic waves of all sorts (light, magnetic field of the earth, UV light, infrared, microwaves, radio waves, etc.) Common knowledge and understanding that not all matter and energy that fills volume can be seen should suffice for documentation.
