Materialism is the view that matter (and energy) are the fundamental realities in the universe. Everything that exists is reducible to, and explicable in terms of, matter. Materialism has always been a popular metaphysical assumption those holding a naturalistic worldview, but in the 20th century materialism found itself challenged by two developments, one was the discoveries being made in quantum physics and the other was its inability to account for human consciousness.
If we think of consciousness, at least in part, as possessing awareness it appears that subatomic particles like electrons exhibit a very rudimentary consciousness. Thus, some thinkers have revived a theory called panpsychism to account for this.
If we can't conceive of how material objects can generate consciousness perhaps it helps to assume that all material objects, down to the tiniest subatomic pieces, are to some degree conscious and that in aggregate are able to comprise conscious beings like ourselves.
I posted several pieces on the topic of panpsychism in the past (2/15/18, 2/16/18/, 2/19/18) and invite the interested reader to check them out.
Neurosurgeon Michael Egnor, who has written a lot about mind and consciousness, has a column at Mind Matters in which he argues that consciousness requires senses and that inanimate objects, lacking senses, must a forteriori lack consciousness.
Perhaps, but as much as I'd like to agree with Egnor I think there's a problem with his argument. Egnor is a theist and if theism is correct then there are pure minds - e.g. God, angels and perhaps the souls of deceased human beings - that are surely conscious but which possess no physical senses. Thus, consciousness would not seem to require, necessarily, a physical sensory apparatus.
This is not to say that I accept the panpsychist's argument, as a perusal of the posts from February of last year will make plain, but I do think there's a problem with our understanding of material substance.
The problem can be found lurking in the materialist's assumption that matter is fundamental and that consciousness is the product of material brains. Maybe things are really the other way around. Perhaps it is mind that is the fundamental substance and that matter is somehow a product of minds. Perhaps matter is to mind as wetness is to water. It's not that every bit of matter possesses mind, as the panpsychist would have it, but rather that matter is an expression of mind.
Imagine, for instance, that, like the images on a computer screen, the fine structure of the physical world is comprised of pixels of exceedingly high resolution. These are not pixels made of chemicals like those on your monitor, rather they're pixels made of information or mind. What appears to us to be material stuff could in fact be a three dimensional manifestation of information flowing from a universal mind somewhat like the pixels on a screen are a two dimensional manifestation of the information flowing from the programmer's mind.
Whatever the case, the days when it seemed obvious that matter is the fundamental reality appear to be waning. As the physicist Sir James Jeans presciently noted back in the middle of the last century, "The world is beginning to look more like a grand idea than a grand machine."
