The existence of distinctions between things remains a highly speculative matter.
G. E. Moore’s famous demonstration of the external world -- “Here is one hand” -- carries weight in the human mind precisely because of its direct appeal to the brute experience of an object as self-evidently real. Nonetheless the here-ness of 'this one hand' continues to struggle to hold up under philosophical scrutiny.
We call "Reductionism" any project which aims to explain one phenomenon purely in terms of another more elementary phenomenon. In this way, reductionism is a game of equivalences – "this is actually that," and so on for everything.
Reductionism runs on the drive to unify everything under a single quality, regardless of whether it be Spirit, Matter, Being, or Nothingness.
Typically, the individual performing this reductive operation conceives of the second phenomenon as more demonstrable in logical or scientific terms, which in our contemporary philosophical context carries the implication of being more "real."
Ironically, G. E. Moore himself was a strong proponent of just such a scientific reductionism. He and his associates in the Vienna Circle were on a quest to purify language from its many non-scientific and unverifiable referents.
Reductionism continues to flourish today, both in its scientific and Platonic forms, but the reductionist's quest to equivocate to the most "real" thing still suffers from the problem that they have yet to find a rock bottom to which things can fully reduce down.
“Turtles all the way down” is nice, but only if you can find the turtle at the bottom of the heap. Otherwise, it remains to be seen if it’s actually turtles all the way down, or simply most of the way down.
This problem of reduction is intimately related to the problem of drawing distinctions. Distinctions can only exist where objects differ, but the reductionist is committed to a vision of the world as a chain of equivalences. How does distinction emerge if all things can be reduced to the same?
Consider this question — are the bacteria living in my gut and which enable me to digest my food me? Or are they not me? I would be unable to break down my food into the necessary nutrients if it weren't for them, so in some true and important sense they are indispensable to my being me.
Where does the line between me and the outside world begin? Human existence cannot be abstracted from the varieties of organisms which make their home on our skin, in our hair, in our mouthes, etc... These are not incidental to who we are. But how do we draw a distinction in either direction? Why does the line fall here and not there?
We can begin to talk about ourselves more as an assemblage, but why include certain parts in the assemblage and not others? Why exclude the atmosphere from the assemblage which is me? After all, can’t all the parts break down to the same fundamental building blocks of existence?
The irony of scientific inquiry has been that it renders lucid one set of phenomena at the cost of lower-order phenomena becoming more obscure.
We say today that we understand how to fly, but we have achieved this only by displacing the complexity from the ‘how’ of flying to the more abstract ‘what’ of the molecules which compose the air.
Atoms were supposed to be the basic building block of reality. They promised something deeper than which it was no longer possible to go. Even the name a-tom (no division) suggests this profound optimism.
And yet, no sooner was the atom posited than we came to understand that it could be split (with catastrophic consequences, no less).
In fact, the modern discipline of physics has experienced a veritable Cambrian explosion of particles smaller than and foundational to the atom. This proliferation of new particles seems to show no signs of abating. The deeper we dig, the more we find, and the harder it becomes to make it all fit together.
Even light itself has not escaped the acidic uncertainty of the scientific endeavor.
Physicists have been unable to ascertain whether light is a wave or a particle, and have instead made an uneasy truce with the paradoxical notion that light exists in an indeterminate state as both and neither before it collapses into one of the two options based on how we humans observe it. Our act of observation forces light "to choose" which of the two it will be, so to speak. This is the best we can say.
Despite how others may feel, reflections of the preceding sort do not engender in me any sense of despair. The un-reality of things does not induce in me any sort of metaphysical vertigo.
Instead, I feel the calm and curious realization that I'm working with a toolbox full of broken tools. I simply have to be creative and adjust my approach.
But, close upon the heels of this sense, I also begin to grasp how the insufficiency of consciousness's engagement with its world provides the very generative character of life.
If all was whole and complete, nothing new would happen. There would be no possibilities to explore, precluding any adventure, learning, or surprise.
One could never intervene in a static Whole, and all the old Greek arguments proving the impossibility of motion would return with a vengeance.
Like Diogenes did to the squabbling philosophers so many years ago, we can simply choose to walk away.
I long ago made the move to replace epistemology with the investigation of consciousness. The reasons are worth elaborating, and I will at a later date, but I'd simply note here that consciousness evokes an operation which active engages the world, as opposed to an epistemology which seeks tests and measures for supposed "knowledge." I do not seek a method of verification, but rather a way of living.