We generally accept the 4 properties that are commonly ascribed to qualia provided by Daniel Dennett as documented in Wikipedia.
A red quale is the quality of our knowledge of things that emit or reflect red light like this image:
The default way to think about color is to use the label ‘red’ in an abstract way. It is a label for a physical reflectance property of something like a ripe strawberry. It is also a label for light of a particular wavelength. It is a label for a particular color channel in a communication system, regardless of what physical representation is being used for the data anywhere in that channel.
But if you want to talk about the differences in all those physical things (reflected light is physically different than reflectance properties of something) that can represent red information, you obviously need terminology that is not ambiguous in this way. To achieve this, we use these new definitions:
Color and colorNESS properties are different. Red is a physical color property and redness is a different colorness quality of our subjective knowledge. It is a physical fact that your subjective knowledge of red things has your redness quality.
For us, if you are thinking about something “structural” or “mathematical” or “abstract” or “relational” you are talking about something different than what we label as a quality. You can model and describe structures, mathematics, abstractions, and relationships. But even if you can detect or describe the behavior or structure or relationships of qualities this tells you nothing of what a quality is like. Qualia are the ineffable natures which can only be subjectively known. If you think of qualities like this, please provide a rigorous definition in a camp, so we can know what you mean, including theoretical possibility of what they are, how you would detect them, come up with new ones, and whether or not it would be possible to “eff the ineffable” and so on.
We assume you can physically detect and describe the behavior of qualities, but their nature, or what they are like, is ineffable. Without a dictionary, you can’t know what an objective description of a quality means. Our Naïve assumptions that we can easily objectively see qualities with our eyes in a “transparent” way, without a dictionary, is mistaken. We do not have a dictionary which connects our objective descriptions of stuff and the subjective qualities we can directly experience. Today, all we know of the color qualities of physical things are the false qualities that seem to be physical properties of things we see. If you think about it rigorously, you realize that something beyond mere percetpion is required to be able to know the nature of a colorness quality. There must be some special process occurring in the brain, which enables us to directly experience or apprehend multiple qualities in a way that enables intelligent computation. This kind of computational binding is what enables us to pick the red strawberries, and avoid the green ones.
Quality is a better term than qualia.
Leading philosophers like Daniel Dennett are known for making claims like: “We don’t have qualia; it just seems like we do.” The only way for a statement like this to make sense, is if the color qualities we know exist are properties of the things we see, since it is irrational to claim the qualities don’t exist. What is needed is a way to communicate so that people will not misinterpret what we are trying to say.
If we use the term quality, solely as a label for the subjective nature of our knowledge of things (i.e. the way things seem) then it becomes easy to communicate why a statement like “it only seems like we have qualia” is self-contradictory to us since seemings are qualities.
Also, functionalists tend to define qualia in a relational way. They don’t care what is representing ‘red’ information, as long as something physically different is representing something different like green information. In other words, functionalists are talking about something different than physical properties or qualities, which are not relational, and do not change in relation to other things. So using the term quality or property avoids this kind of miss communication where functionalists are thinking of something different when you use the term qualia. Functionalists require definitions to get between physical properties and meanings. But you don't need a dictionary to know the properties of glutamate.
As documented here, physicists don’t yes understand the qualities of things. Obviously physical reality is composed of things with lots of different qualities. The problem is, we don’t yet know which of all our objective descriptions of stuff is a description of any particular color quality. If anyone still disagrees with this, you can show them how you could put a red/green signal inverter immediately after the retina, as illustrated by the C system in this image:
You can then point out that both B and C represent red things with your greenness quality. You can then ask them which quality is the true quality of ‘red’ things. It is important for people to realize that science can’t account for the greenness quality experienced by the C system, while red light is being detected by the retina. Once one understands these things, it becomes clear that the term ‘qualia’ is redundant and leads to the possibility that you will be misinterpreted when you use an additional term like qualia.
In summary, if you use the term quality, instead of qualia, and people understand that there is no objective evidence that anything out there we see has any particular quality, then you are far less likely to be miss interpreted when you say something like: We don’t yet objectively know the color quality of anything. Today, all we know are the false colored seeming qualities of things.