We can’t know everything. In fact, we necessarily can’t know everything. That is the key underlying point of a recent book by William Egginton titled The Rigor of Angels: Borges, Heisenberg, Kant, and the Ultimate Nature of Reality. Egginton audaciously attempts to make the point by examining the thought and work of three disparate intellectual giants. He is least successful, I believe, in fitting the writer Jorge Luis Borges into the triangle with the other two; but the attempt is at least partly successful and well worth the effort.
All three thinkers are saying, in effect, that reality is a bitch. It is essentially (but not totally) unknowable. In Kant, the unknowable includes what extends beyond our powers of reason and observation: the Ding-an-Sich or Thing-in-Itself that is the world apart from all possible perceptions of it. Think of looking at a cube: you can never see all six sides at one time. But reason tells you, more or less, what’s there that you cannot see.
For the German physicist Werner Heisenberg, what’s unknowable is on the subatomic level. Heisenberg, along with fellow physicists Max Born and Max Planck (the father of quantum theory) among others, argued for quantum mechanics against the resistance of two other scientific geniuses, Albert Einstein and Erwin Schrödinger.
I won’t go into the details, because they are complicated (of course), and mostly elude me. The physics often surpasses one’s ability to visualize it – which is precisely what Heisenberg was saying: we can’t visualize quantum mechanics or its strange corollaries, such as “spooky action at a distance” where particles affect one another across space and time. It’s hard enough just to visualize spacetime as a single entity. If you can do that, draw me a picture.
What does make sense to me, on a mundane level, is that we cannot both measure and locate elementary particles at the same time, because trying to do so alters their location or velocity. That is Heisenberg’s famous Uncertainty Principle, and I kind of get it. I come away with glimmers of understanding, but the glimmers are rewarding. And one can always hope for more and brighter glimmers. That’s why I keep reading books like Egginton’s, and Carlo Rovelli’s, and the many articles in Aeon.co on physics that are semi-accessible.
So what is reality? The answer isn’t that reality doesn’t “exist,” or that life is an illusion. If it were an illusion, something or someone would have to exist to have it. But I find several takeaways.
First, there are things that we know we cannot know. There are seemingly absolute limits to the human mind (not just the inability to see all sides of a cube at once, but it's a useful metaphor). This is because, as Egglinton notes, to know anything is to make comparisons across time and space. “To know, perceive, or imagine anything at all requires us to span points in space and time, to be at some point in space-time and not another one, and then make a bridge from one to the other.”
In the very big scheme of things and the very small scheme of things, time and space and subatomic particles either a) don’t exist, b) exist only as tools of the human mind – as Kant put it, they are the “forms,” respectively, of the inner sense and the outer sense; or c) exist in a way that we simply cannot fathom. Maybe it’s our language that limits us – for example, to categorizing photons as either waves or particles. Maybe they are more accurately something else.
In light of these limits, it’s astonishing that our greatest scientists were able to discover both relativity and quantum mechanics; and that relativity has been scientifically proven and quantum mechanics seems likely to soon generate vast technological advances in the area of quantum computing – even though ultimately the two theories don’t quite match up. They are more like particles that we can measure or locate separately but not together.
Another takeaway is that the more bizarre or inaccessible reaches of reality don’t affect us, at least not yet. On the supra-atomic level, we still exist in a happily retrograde Newtonian world where apples fall and things hold together. If the subatomic and supra-atomic levels of nature don't seem to live by the same rules, so much the worse for our scientific understanding and mental capacities. The smart people are still working on it.
A third conclusion, for me at least (which I’ll follow up in my next post on metaphysics) is that “existence” and “reality” are not things, but human concepts codified in language. (Actually, I already knew that.) It is up to us to define and control our language to convey meaning and describe the world. In that sense, we are in the driver’s seat. But is language a limiting factor? Or just a projection of the limits of our minds?
As I suggest in Inside the Liberal Arts, the universe can’t, in any meaningful sense, be “more complex than we can ever understand.” Complexity is not a property of the universe, but a conceptual tool for understanding it. A very useful tool, but a human one. Maybe, in some sense, what we can’t understand doesn’t exist.
Put another way: all metaphysics is ultimately pragmatic: it’s about what is most useful and workable in describing the mind and the world. So, if reality exists, if there is any existence at all, it's because saying so helps us to think and to communicate. We didn’t create the universe, but we drive the car of thought and language.
If there’s Someone or Something Else in a bigger driver’s seat, it’s highly likely that we will never be able to identify or describe it. But as our most brilliant minds have shown, you can’t keep us humans from trying.