Preface

This was written as https://www.quora.com/Why-do-we-still-have-problems-understanding-what-consciousness-is-Can-we-find-the-ultimate-answer/answer/Anil-Mitra-2.

Here, I will be improving the foregoing answer.

Answer

When we ask “what consciousness is”, it may occur to us that it is very different from what we call matter.

So some questions come up

Is consciousness or subjective awareness in all its forms different from matter? And if so, how is it related to matter. It must be related to matter in some way for we always find consciousness in material organisms. I don’t insist on that ‘always’ as a metaphysical truth but it does seem empirical.
In turn, what is matter? Our first understanding is that it is something we sense. But we also notice patterns of behavior and this begins the science of physics. Our ultimate understanding of matter today is primarily in quantum theory and secondarily in relativity. Are the quantum properties necessary? Or is classical physics sufficient to understanding mind? I suspect quantum theory is necessary but perhaps it is not enough—a deeper (or lateral) theory may be needed. Neurology may be sufficient but if consciousness or parts of it depend on indeterminism, fundamental physics may be necessary.
So it’s not clear that we have a sufficient grasp of physics (and so on) to explain consciousness—to say what consciousness is—in material terms. However, at least as a first approximation, consciousness appears to appear in brains.
But let us imagine that deep down matter is all there is (‘substance’) and we have understood it fully. Its not altogether clear that we will but let us assume so (if we hadn’t understood it fully we would not be justified in saying that it is all there is). Now in that case, it is obvious in a very general sense what consciousness must be. It must be something that we might call the ‘interiority’ of matter: matter in self-interaction. After all, if matter is all there is and if, as we tend to agree, there is consciousness, then consciousness must be a function of matter and most likely matter in interaction. We might say that consciousness arises from matter but that would be inaccurate; rather, consciousness is matter but from another perspective.
What interaction? I don’t think we know. How does consciousness get to be so intense in humans and other animals, how does it have its variety—cognition, emotion, willing, perception… we know some things but not at a very fundamental level.
That is, if you accept the foregoing material argument, then we do have a good grasp on one aspect of consciousness—what has been called the hard or philosophical problem of what consciousness is in substance or material terms. I think the hard problem is hard only because our philosophy has been bad. On the other hand we are far from an adequate address of the easy or scientific problem. Perhaps seeing consciousness in the right way as an aspect of matter may help with the science.
Is consciousness emergent? I don’t think consciousness itself is emergent. I do think its intense and varied qualities as they appear in animals is emergent but it is the detail and not the substance (mind from matter) that is emergent. But it does not seem to me that so far emergence has done any significant explaining in consciousness.
Meanwhile I think approaches like ‘Integrated Information Technology’ are a good idea. The idea there is to put aside the question of what consciousness is and focus on what it does and finding information processing models for it. It’s a good idea because it doesn’t make sense to let our ignorance about the material details to hold up studies. On the other hand I don’t think IIT is a replacement for fundamental studies in the neurology of conscious / subconscious / processing.
Summary. I think we have a decent account of the fundamental thing that consciousness is in very general terms. But we await a mature detailed scientific account of consciousness.
Postscript. An illustrative insert on free will. Think about will. What is it? On the material ‘side’ in the above description, it is matter doing its thing. On the consciousness side it is consciousness-preconsciousness doing their thing.

Experiments show pre-consciousness wins? The experimenters themselves agree that that’s but one interpretation. In any case, the experiments concern simple operations. Life is a long operation.

Now what about the free part of free will. It is unclear to me why we would have will if it weren’t free—what would it’s adaptive advantage be? It seems it must be free for adaptive advantage. But if free then there must be indeterminism.

The counterargument is that randomness cannot produce structured responses (David Hume noted this). But that is a poor description of what is going on. The organism is structure. Indeterminism is a small part of it. It produces small changes; intelligence notices which are adaptive (‘new ideas’ or elementary ‘new actions’).

That is freedom of will occurs at the boundary between structure and indeterminism

So you can see, at least tentatively, the open ended material model is giving us a good general handle on consciousness and showing us at the same time that some of its processes must be indeterministic—just as in quantum mechanics structure arises out of probabilistic process in bound states.

For more on indeterminism in the world, see Anil Mitra's answer to How can free will or determinism be scientifically/mathematically deduced or proved?.