[W]e need to briefly explore what the hard problem of consciousness is, and to do that we need to look at the metaphysical philosophy of materialism. Simply stated, this asserts that everything is made of matter, of physical stuff. You may wonder why such a seemingly obvious and self-explanatory statement requires the title of a metaphysical philosophy. The reason is that materialism isn’t just saying that there are physical things, it is saying everything is physical. Materialism is saying that the thoughts you are having now are physical; it is saying that the curious and unique mix of emotions you are subjectively experiencing at this very moment are purely and solely physical material things. And it is saying that the awareness that witnesses all these subjective feelings is physical. This no longer seems so obvious, does it?I'm in agreement with all of this. They are saying the material stuff out there -- trees, rocks, stars etc -- is the same type of stuff as toothache, feeling angry, or indeed the experience of seeing said trees, rocks and stars. And the experiencer or self who undergoes all these experiences is also material! But what is the cash value of this, what does it actually mean? My experiences, emotions, thoughts etc don't have any attributes we conceive the material world as having -- so no shape, no size, no mass, no electric charge etc. Moreover, our consciousness appears to be invisible. I cannot see your consciousness, you cannot see mine. It can only be inferred from our behaviour, not directly detected.
Not only does it perhaps seem a little strange to assume that all our mental, emotional and spiritual experiences, and the subjective experiencer, are actually objective, external and physical, materialists have absolutely no idea, even in principle, how matter could possibly create our rich inner life of conscious awareness and experience. This is what is referred to as the hard problem of consciousness.Their solution is often to identify consciousness with neural processes or, alternatively, what such processes do NB it is not being said here that neural processes cause or elicit conscious experiences, but rather our conscious experiences are nothing but such neural processes. If you think this is utterly nonsensical, then you get it, it is. A bit like saying ice cream is literally one and the same thing as sand, or identifying any 2 completely different objects as being one and the very same object.
But what of science? Isn’t the indisputable and phenomenal success of science and technology proof that materialism is an extremely successful theory? No. Science is agnostic on metaphysical philosophy. The scientific method and all the advances and technological breakthroughs that follow, work perfectly well regardless of your philosophical beliefs. That is, in fact, its strength: it relies on empirical data, not belief.Yes, material reality exhibits patterns, science describes such patterns using mathematics. How could that possibly connote that consciousness is material? It seems to me to be similar to someone exclaiming that given how successful metal detectors are at finding metal objects, anything that is not registered by the detector, such as plastic objects, must be really metal in disguise or else illusory. It's that silly.
The metaphysical theory that everything is matter is a philosophy, not a scientific fact. But we can go further and say that even the assumption that there is any matter at all, is equally a theory and a philosophical assumption, not a scientific fact. The idea that there is physical matter outside of our conscious experience is just that, an idea. We only know for sure that we have subjective experience; we cannot know for sure what constitutes that experience. The only thing we know for sure is our immediate experience of being subjectively aware. Everything we can ever possibly know can only be known by us within and via the medium of our subjective experience.Yes, we cannot know that a material reality exists at all if what we mean by a material reality is material stuff having a full-blooded existence entirely independently of consciousness. One alternative is Berkeley's Idealism otherwise known as subjective idealism. I talk about Berkeley's subjective idealism here (this isn't quite the same as Kastrup's idealism).
In contrast to this idealist view of the world, a materialist philosophy posits an external and objective physical world that is not directly knowable. Our only experience of such a world, if it exists at all, is through our subjective experiences. The idea that there is such an objective external physical world is an abstraction thought up by consciousness. And it is an abstract theory that is becoming less and less supported by the results of our best scientific experiments in quantum mechanics.Yes, for example, is this material external world coloured? Are there sounds and smells out there? In other words, is this material reality similar to our perceptions of it? Not according to the standard scientific story. To be honest, I do not think you have to be an idealist to emphatically reject this scientific story. I regard it as preposterous this notion that objects are not really coloured but are a creation of the mind.