David Kolb

Parmenides, Nagarjuna and Carlo Rovelli walk into a bar…

The bar is empty, said Nagarjuna
There’s only one here, replied Parmenides,
If we lean on one another we can see what’s around, said Carlo, as he ordered each of them a quantum of action.

In this post I watch Parmenides haunting science through the ages and ask whether quantum mechanics might exorcise that haunting.

The obstinate pre-Socratic philosopher Parmenides denied that the world of many changing things we see around us was real. Teaching him in a Greek philosophy course is difficult because unlike other Pre-Socratic thinkers he presents no nice imaginative picture of the cosmos. Instead he provides a conceptual argument that leads to crazy conclusions. He applies a stark criterion: anything that truly is real has to be totally positive. Reality either is or it isn’t, and if it is then it should be fully itself.

Parmenides declared (in the middle of the fifth century BC) that “The judgment to be made about these matters is: Is or Is Not” [hē de krisis peri toutōn en toide estin: estin e ouk estin]. “Being is complete: in fact it does not need anything; otherwise it would lack everything…. Being is not-generated and not-dying, entire and motionless and without limit; not sometimes it was nor sometimes it will be, because it is now, whole together, one, continuous.” In short, basic reality “necessarily is entirely or it is not at all” [houtōs ē pampan pelenai khreon estin ē oukhi].

“What Is Not is absolutely unutterable and unthinkable.” Parmenides claimed that negative statements don’t refer to realities. Nothing negative can be said of true reality. If in any way an item is not fully what it is (by changing, for instance, so it is never fully itself, or by being one of a plurality and so not-something-else) then it is not real because it is infected with non-being, and true reality must be an altogether yes/no issue. Full, complete, just itself, in need of nothing to complete its existence. Unchanging and eternal.

What then does Parmenides say about our daily world of many changing entities we see coming and going out of being? “Illusion”, “unreal”.

Teaching Parmenides is difficult because he offers an austerely conceptual argument. When I go on to show how Plato and Aristotle criticized Parmenides, my students breathe a sigh of relief. His crazy ideas can be left behind.

Bu they are wrong. It’s true that no one accepts Parmenides’ conclusions as he states them, yet almost everyone is haunted by his underlying conviction about the positive quality of basic reality. Don’t real things have to be wholly themselves, positively full and compete?

Parmenides realized his conclusion was outrageous so he supplemented his conceptual argument with a story that pictured a world made of different kinds of matter combining and recombining, a story he says is false. No one is sure what he meant that story to do.

But the story did suggest strategies later thinkers adopted. Two levels: affirm a basic level of solid unchanging indestructible entities, and then allow them to combine with one another to construct our changing world. This is the strategy of the Greek atomists, who accept Parmenides’ criterion for true reality. They multiply his one full being. They sharply distinguish positive solid full physical being from negative empty space. The individual atoms of Democritus and the Epicureans are each a Parmenidean perfectly positive real being. Each atom is independent, full, complete in itself, needing nothing. They fill their space and contain no empty “void” inside them, no fracture lines. So they can not be cut, have no parts, never change, and have no connection with other atoms except external hook-ups where their spines or shapes become entangled. These individually unchanging atoms assemble into the changing beings that we know, but any one atom by itself remains utterly untouched by all the external combining and bouncing. It never alters; it just is. Things happen around it but they have no effect upon its immovable full reality. Just as Parmenides wished.

Plato and Aristotle make a different move. They develop better theories of meaning and negation, so that a negative statement is not assigning a non-entity to a real thing, but talking about a thing’s difference from something else. So negative statements about a thing do not impugn its yes/no reality. Change and plurality can be safely affirmed. This allows Plato and Aristotle to describe two levels or kinds of beings, one dependent on the other, though not in the straightforward spatial way the atomists described the relation of their two levels.

Plato gives an account of a world that contains many changing beings. Yet Plato pays his dues to Parmenides by agreeing that basic fundamental reality has to be eternal, unchanging, solidly itself but solidly material. His many changing beings depend on and borrow their reality from the fully positive platonic immaterial Forms. Each of these Forms or patterns is purely itself. But there are many of them, and they stand in complex inner relations to one another. So Plato’s most basic entities meet a modified version of Parmenides’ criteria that allows levels of more or less reality, with internal complexity within the fully real.

Aristotle too goes against Parmenides by offering a cosmos with changing beings which have potentials they are on the way to actualizing: puppies becoming dogs, plants growing, the elements moving to their assigned places. But in order to guarantee the permanence of his changing cyclic universe Aristotle adds a level of super-real beings, his unmoved movers, and these do meet Parmenides’ demands: they are fully positive, always completely actual with no unrealized potentialities, and they do not interact with other beings (which would bring passivity and change). Totally self-involved, they simply Are and in their perfection they function as goals that keep the universe going.

So both Plato and Aristotle accept from Parmenides that to account for the reality of the cosmos there must be some component or level which is totally positively real, not on the way to becoming something else, fully and always solidly itself. Though people had found more complex ways to think that fullness through thatey allowed for internal multiplication and complication within or depending on those totally positive beings.

Once the monotheistic religions took up Greek philosophy they reaffirmed Parmenides insofar as an eternal perfect god became the origin and support of the changing cosmos. (I’m passing over the complications added by the Neo-platonists.)

And when religion was challenged in the scientific revolution Greek Atomism reappeared, with its solid atoms again playing the foundational role. This kept alive Parmenides’ image that full physical reality should be solid and, in Whitehead’s words, “simply located”. That is, little bits of matter construed as self-subsistent and self-individuated and bearing intrinsic properties. (Indeed, Parmenides also has other atomistic descendants. Not just those who find basic unchanging simply located items of physical reality but also those who find with David Hume basic psychological impressions or perceptions which are each one simple, independent of all others, with no internal relationships, each a perfect Parmenides one being. (For instance the basic elements of David Lewis’ Humean ontology.)

Today, though, our empirical theories of the atom bring us new particles surfing electromagnetic and many other fields. Fields bring complications and connections to the pristine Greek atoms. Our equations have left behind both the tangles of those shaped Epicurean atoms as well as Newton’s smoothly gravitating spheres. Our atoms have parts that act as both waves and particles, jump energy levels, entangle with and transform into one other, and pass through two slits at once. Yet despite being informed about these odd developments in the new theories, we still keep on picturing atoms as miniature solar systems with particles as hard little balls bouncing and rotating. Popular science writers keep despairing of our attachment to such antique pictures and keep exhorting us to upgrade our outdated images of fundamental particles.

I think, though, there is more resisting that upgrade than difficult math and our lazy imaginations. I think our imagination holds on to the Parmenides criterion: at some level basic reality has to be composed of things which are fully real, solidly fill their space, and are acted upon only externally. We worry that if we don’t insist on such a foundation, everything may topple into the abyss of non-being.

This Parmenidean faith gets reinforced when general relativity, our Big physical theory, offers us more or less what Parmenides sought. Einstein’s space-time, taken as a whole, is totally full and unchanging. Nothing happens in space-time as a whole. Time as commonly understood is an illusion. General relativity comes out and says what Parmenides told his contemporaries: a truth that denies our most evident experience, and like him it doesn’t deign to explain how that experience fits in. The best we get is a promissory note that when brain science is more developed, the temporal flow of our experience will turn out something like a product of brain states referring to one another.

Then comes Quantum Mechanics, our other Big theory, where some thinkers look for rescue. It is known that for many deep reasons it’s hard to reconcile the mathematics of quantum mechanics with general relativity.They can’t just be set alongside one another. GR is classically continuous and exact, QM discrete and probabilistic. Time is treated very differently in the two theories. But again I wonder if a Parmenidean bias may also be at work: it may be hard to hold on to the solid full unchanging positivity of general relativity if we add QM’s seeming lack of solid fully real and independent particles. Quantum entanglement and superposition seem to go against the Parmenidean self sufficiency of each entity.

The question around the bar, then, is whether QM affirms a base level of independent solid realities, as Parmenides would demand. That depends on what QM is saying about basic realities. But that, no one knows for sure.

Interpretations of quantum mechanics that derive from Copenhagen and QB treat the Schrödinger wave equation as an instrumental device for making prediction or a report on our knowledge. They take no side on Parmenides, neither affirming nor denying.

On the other hand, interpretations that see the wave equation as representing a physical reality mostly come down on the side of Parmenides. Spontaneous collapse, superdeterminism, and decoherence interpretations can make their peace with him, at least after the collapse. The many worlds interpretation is Parmenidean in that the many worlds are each composed of perfectly definite atomic particles. Or, alternatively, because the wave function is seen as describing all of space time like a pond crossed by many intersecting patterns of waves, which moves QM towards Einstein’s Parmenidean fullness.

But Carlo Rovelli came to the bar today because in his recent book Helgoland he argues for an interpretation of quantum mechanics which looks as if it might exorcise Parmenides ghost. He argues for a “relational” account of QM. Quantum particles don’t just exist on their own; they exist in relation to others, in interactions, and he even leads us to Nagarjuna.

Nagarjuna had argued, somewhere around 200 AD, against what he called sva-bhava, self-being, solid independent self sufficient entities. The sort of things we think we see around us every day. The sort of things we think we ourselves are. These things are “empty,” Nagarjuna says. Our everyday world is an illusion created by our trying to freeze and cling to what is in reality an evanescent interdependent process where brief phenomena dependently arise and pass away.

What, though, is that ‘interdependence”and “interrelation”? Is it primarily epistemological, a limitation on our knowleldge, that is, that we must inquire to one being through another that qualifies the response? That’s not too surprising, a kind of skepticism. Or is it ontological: that the truly real fundamental beings don’t exist in isolated individual Parmenidean solidity, but only in some interrelated net, open or closed. That would challenge Parmenides’ demand.

Rovelli in various texts seems to be asserting both of these, and while popular interpretations of Nagarjuna often see him as advancing the ontological claim, scholarly readings tend to see him making the epistemological claim, but then in addition going on to argue that there is no reason to go on asking Parmenides’ question. I think that Rovelli wants to end up there as well.

But are we perhaps still owed some ontological account of interaction?. Things have to be somehow definite so that the interaction is definite. When you measure an electron’s spin you get a number, you don’t get cauliflower or a mongoose. Figuring out the mode of being of that definiteness has fueled centuries of debate. Avoiding Parmenides in that debate remains a task for contemporary philosophies of process and event: Bergson, Whitehead, Deleuze, some of OOO (object oriented ontology), and some relaxed versions of Hegel.