Helgoland by Rovelli, Erica (ebook reader below 3000 .txt) 📗

this: the world is not divided into stand-alone entities. It is we who divide it into objects for our convenience. A mountain chain is not divided into individual mountains: it is we who divide it up into parts that strike us as in some way separate. A countless number of our definitions, perhaps all of them, are relational: a mother is a mother because she has a child; a planet is a planet because it orbits a star; a predator is such because it hunts prey; a position in space is there only in relation to something else. Even time exists only as a set of relations.116

None of this is new. But physics has long been asked to provide a firm basis on which to place relations: a basic reality underlying and supporting this relational world. Classical physics, with its idea of matter that moves in space, characterized by primary qualities (shape) that come before secondary ones (color), seemed to be able to play this role. It appeared to furnish the primary ingredients of the world that it was possible to think of as existing in their own right as the basis of the interplay of combinations and relations.

The discovery of the quantum properties of the world is the discovery that physical matter is not capable of fulfilling this role. Fundamental physics does provide an elementary and universal grammar for understanding phenomena, but not a grammar consisting of simple matter in motion, with its own primary properties. The contextuality that permeates the world reaches this elementary grammar. There are no elementary entities that we can describe except in the context of their interaction with something else.

This leaves us without a foothold, no place to stand. If matter with definite and univocal properties does not constitute the elementary substance of the world, and if the subject of our knowledge is a part of nature, what is the world’s elementary substance?

To what can we anchor our conception of the world? From where can we begin? What is fundamental?

The history of Western philosophy is to a large extent an attempt to provide an answer to the question as to what is fundamental. It is a search for the point of departure from which everything else follows: matter, God, the spirit, the atoms and the void, Platonic Forms, a priori forms of intuition, the subject, Absolute Spirit, elementary moments of consciousness, phenomena, energy, experience, sensations, language, verifiable propositions, scientific data, falsifiable theories, the existence of the being for whom being matters, hermeneutic circles, structures . . . A long list of candidates, not one of which ever managed to achieve a universal acceptance as ultimate foundation.

The attempt by Mach to take “sensations” or “elements” as foundational has inspired scientists and philosophers, but in the end does not seem any more convincing than others. Mach rails against metaphysics, but he effectively produces his own metaphysics—lighter and more flexible, but a metaphysics nonetheless—of elements and functions. Mach’s is a phenomenal realism, or a “realist empiricism.”117

In my own attempts to make sense of quanta for myself, I have wandered among the texts of philosophers in search of a conceptual basis with which to understand the strange picture of the world provided by this incredible theory. In doing so, I have found many fine suggestions and acute criticisms, but nothing wholly convincing.

Until one day I came across a work that left me amazed. I will end this chapter, which does not have any conclusions, with a light account of this encounter.

I did not come across it by chance. When speaking about quanta and their relational nature, I had frequently met people who asked: Have you read Nāgārjuna?

When I’d heard my umpteenth “Have you read Nāgārjuna?” I decided to go ahead and read it. Though not widely known in the West, the work in question is hardly an obscure or minor one: it is one of the most important texts of Buddhist philosophy, so it was only due to my personal ignorance of Asian thought (not so uncharacteristic in the West) that I was unaware of it. Its title is one of those never-ending Sanskrit words—Mūlamadhyamakakārikā—translated in numerous ways, including The Fundamental Wisdom of the Middle Way. I read it in a translation with commentary by an American analytic philosopher. It has made a profound impression upon me.118

Nāgārjuna lived in the second century ce. There have been countless commentaries on his text, which has been overlaid with interpretations and exegesis. The interest of such ancient texts lies partly in the stratification of readings that gives them to us enriched by levels of meaning. What really interests us about ancient texts is not what the author initially intended to say: it is how the work can speak to us now, and what it can suggest today.

The central thesis of Nāgārjuna’s book is simply that there is nothing that exists in itself independently from something else. The resonance with quantum mechanics is immediate. Obviously, Nāgārjuna knew nothing, and could not have imagined anything, about quanta—that is not the point. The point is that philosophers offer original ways of rethinking the world, and we can employ them if they turn out to be useful. The perspective offered by Nāgārjuna may perhaps make it a little easier to think about the quantum world.

If nothing exists in itself, everything exists only through dependence on something else, in relation to something else. The technical term used by Nāgārjuna to describe the absence of independent existence is “emptiness” (śūnyatā): things are “empty” in the sense of having no autonomous existence. They exist thanks to, as a function of, with respect to, in the perspective of, something else.

If I look at a cloudy sky—to take a simplistic example—I can see a castle and a dragon. Do a castle and a dragon really exist up there in the sky? Obviously not: the dragon and the castle emerge from the encounter between the shape of the clouds and the sensations and thoughts in my head; in