That's a great title: "What is Reality?"
It gets right down to the nitty-gritty of what life is all about. Being real. Whether we live only once, or have an opportunity to live another physical or metaphysical existence, making the most of these precious human moments means really living them.
So I leapt to open an issue of New Scientist magazine that had "The Big Questions" emblazoned on the cover. "What is Reality?" is the biggest of the big in my opinion. And seemingly that of the magazine's editors also, since they featured Roger Penrose's essay on this subject in the numero uno position.
I've read a couple of Penrose's books. Can't say that I understood them even halfway completely, but the guy is an Emeritus Professor of Mathematics at the University of Oxford. And I struggled with high school trig.
Nonetheless, I enjoy Penrose's ability to meld his profound scientific and mathematical knowledge with deep philosophical musings. Here's his entire article, which is eminently readable.
On this blog my posts and visitor comments often touch on the question of what's really real. I lean toward the objective reality side; others tilt toward subjectivity, seemingly arguing that whatever reality is, it can't be separated from the consciousness that's aware of it.
Penrose sets up a straw man sort of argument at the beginning of his piece. Like many politicians he utilizes a "Some say" approach that is one of the few things in his essay I don't agree with. I've never heard anyone say the following, just as I've never heard anyone support the "Some say we shouldn't fight the terrorists who hit us on 9/11" phrase so beloved by Bush and Cheney.
Some might even feel driven to the view that one's own particular conscious experience is to be regarded as primary, and that the experiences of others are themselves merely things to be abstracted, ultimately, from one's own sense data.
He correctly rejects this solipsistic position — which is pretty much held only by the seriously mentally ill. But he also rejects a much more common belief, one probably shared by some who are reading these words.
Even if such a solipsistic basis is not adopted, so that the totality of all conscious experience is taken as the primary reality, I still have great difficulty. This would seem to demand that "external reality" is merely something that emerges from some sort of majority-wins voting amongst the individual conscious experiences of all of us taken together.
I'm with Penrose. There's just too much evidence of an astonishing regularity underlying the universe. Of course, it isn't so astonishing when we consider that if reality was unpredictably chaotic, life as we know it couldn't exist. (This basically is the Anthropic Principle, which points out the obvious: if the universe wasn't suitable for life, we wouldn't be here wondering why the universe is suitable for life).
Among the basic laws of physics that we know – and we do not yet know all of them – some are precise to an extraordinary degree, far beyond the precision of our direct sense experiences, or of the combined calculational powers of all conscious individuals within the ken of mankind.
…It would be a mistake to think of the role of mathematics in basic physical theory as being simply organisational, where the entities that constitute the world just behave in one way or another, and our theories represent merely our attempts – sometimes very successful – to make some kind of sense of what is going on around us.
…To me, such a description again falls far short of explaining the extraordinary precision in the agreement between the most remarkable of the physical theories that we have come across and the behaviour of our material universe at its most fundamental levels.
This is the point where a lot of spiritually-inclined people part company with science. But not me. Mathematics is able to describe and predict how many, if not most, physical systems behave (in theory, at least). I've got no problem accepting that the same likely is true of you, and me (in theory, at least).
It's natural to think of ourselves as special, somehow outside the laws that govern material reality. The structure of space and time, gravity, moving bodies, electromagnetism, quantum mechanics, fluid dynamics, nuclear forces—these phenomena and so much more can be modeled with remarkable precision by scientific theories which are primarily mathematical.
To me, that's beautiful. It reflects the unity and order of the cosmos. And I'm a part of it. Yes, I see the world subjectively, as do we all. But underlying the vagaries of individual consciousness is a whole other order of being that Penrose points us toward.
It isn't really physical, because materiality fades away once one reaches the foundational quantum world.
Whether we look at the universe at the quantum scale or across the vast distances over which the effects of general relativity become clear, then, the common-sense reality of chairs, tables and other material things would seem to dissolve away, to be replaced by a deeper reality inhabiting the world of mathematics.
You could look upon this as the mind of God. But I'd rather not. It is what it is. Which we don't know, because there's debate over whether mathematics simply describes how the stuff of physical reality operates, or whether there's another plane of reality that the mathematical laws of nature emanate from.
I'm attracted to the second option. Like most mathematicians, so is Penrose.
Might mathematical entities inhabit their own world, the abstract Platonic world of mathematical forms? It is an idea that many mathematicians are comfortable with. In this scheme, the truths that mathematicians seek are, in a clear sense, already "there", and mathematical research can be compared with archaeology; the mathematician's job is to seek out those truths as a task of discovery rather than one of invention.
To a mathematical Platonist, it is not so absurd to seek an ultimate home for physical reality within Plato's world.
And that is decidedly "spiritual," though it's difficult to discern much difference between mathematicality and spirituality if one accepts Penrose's basic premise: that reality is mysteriously both objective and tied to the conscious subjectivity of those who experience it.
We do not properly understand why it is that physical behaviour is mirrored so precisely within the Platonic world, nor do we have much understanding of how conscious mentality seems to arise when physical material, such as that found in wakeful healthy human brains, is organised in just the right way.
Nor do we really understand how it is that consciousness, when directed towards the understanding of mathematical problems, is capable of divining mathematical truth. What does this tell us about the nature of physical reality? It tells us that we cannot properly address the question of that reality without understanding its connection with the other two realities: conscious mentality and the wonderful world of mathematics.