By Carlo Rovelli
P.148
Let us turn to ourselves, then, and to the role we play in relation to the nature of time. Above all else, what are we as human beings? Entities? But the world is not made up of entities, it is made from events that combine with each other… So what, then, am ‘I’?
In the Milinda Panha, a Buddhist text written in Pali in the first century of our era, Nagasena replies to the questions of King Milinda, denying his existence as an entity:
King Milinda says to the sage Nagasena: What is your name, Master? The teacher replies: I am called Nagasena, o great king; Nagasena is nothing but a name, a designation, an expression, a simple word: there is no person here.
The king is astonished by such an extreme-sounding assertion:
If no person exists, who is it then who has clothing and sustenance? Who lives according to the virtues? Who Kills, who steals, who has pleasures, who lies? If there is no longer an actor, neither is there good or evil any longer…
And he argues that the subject must be an autonomous being that is not reducible to its component parts:
Is it the hairs that are Nagasena, Master? Is it the nails or the teeth or the flesh or the bones? Is it the name? Is it the sensations, the perceptions, the consciousness? Is it none of these things?…
The sage replies that ‘Nagasena’ is effectively none of these things, and the king seems to have won the discussion: if Nagasena is none of these, then he must be something else – and this something else will be the person Nagasena who therefore exists.
(…)
We are processes, events, composite and limited in space and time. But, if we are not an individual entity, what is it that founds our identity and its unity?
(…)
There are different ingredients that combine to produce our identity. Three of these are important for the argument of this book.
1.
The first is that every one of us identifies with a point of view in the world. The world is reflected in each one of us through a rich spectrum of correlations essential for our survival. Each of us is a complex process that reflects the world that is strictly integrated.
2.
The second ingredient on which our identity is based is the same as for the chariot. In the process of reflecting the world, we organize it into entities: we conceive of the world by grouping and segmenting it as best we can in a continuous process that is more or less uniform and stable, the better to interact with.
(…)
It is the structure of our nervous system that works in this way. It receives sensory stimuli, elaborates information continuously, generating behaviour. It does so through networks of neurons which form flexible dynamic systems that continuously modify themselves, seeking to predict – as far as possible – the flow of information intake.
(…)
If this is so, then ‘things’, like ‘concepts’, are fixed points in the neuronal dynamic, induced by recurring structures of the sensorial input and of the successive elaborations. They mirror a combination of aspects of the world that depends on recurrent interactions with us.
(…)
In particular, we group into a unified image the collection of processes that constitutes those living organisms that are other human beings, because our life is social and we therefore interact a great deal with them. They are knots of cause and effect that are deeply relevant for us. We have shaped an idea of a ‘human being’ by interacting with others like ourselves.
I believe that our notion of self stems from this, not from introspection. When we think of ourselves as persons, I believe we are applying to ourselves the mental circuits that we have developed to engage with our companions.
(…)
The experience of thinking of oneself as a subject is not a primary experience: it is a complex cultural deduction, made on the basis of many other thoughts. My primary experience – if we grant that this means anything – is to see the world around me, not myself. I believe that we each have a concept of ‘my self’ only because at a certain point we learn to project on to ourselves the idea of being human as an additional feature that evolution has led us to develop during the course of millennia in order to engage with other members of our group: we are the reflection of the idea of ourselves that we receive back from our kind.
3.
But there is a third ingredient in the foundation of our identity, and it is probably the essential one – it is the reason this delicate discussion is taking place in a book about time: memory. We are not a collection of independent processes in successive moments. Every moment of our existence is linked by a peculiar triple thread to our past – the most recent and the most distant – by memory. Our present swarms with traces of our past. We are histories of ourselves. Narratives. I am not this momentary mass of flesh reclined on the sofa typing the letter ‘a’ on my laptop; I am my thoughts full of the traces of the phrases that I am writing; I am my mother’s caresses, and the serene kindness with which my father guided me; I am my adolescent travels; I am what my reading has deposited in layers in my mind; I am my loves, my moments of despair, my friendships, what I’ve written, what I’ve heard; the faces engraved on my memory. I am, above all, the one who a minute ago made a cup of tea for himself. The one who a moment ago typed the word ‘memory’ into his computer. The one who just composed the sentence that I am now completing. If all this disappeared, would I still exist? I am this long, ongoing novel. My life consists of it.
It is memory that solders together the processes scattered acorss time, of which we are made. In this sense we exist in time. It is for this reason that I am the same person today as I was yesterday. To understand ourselves means to reflect on time. But to understand time we need to reflect on ourselves.
(…)
To a large extent, the brain is a mechanism for collecting memories of the past in order to use them continually to predict the future. This happens across a wide spectrum of time scales, from the very short to the very long.
(…)
In Book XI of the Confessions, Augustine asks himself about the nature of time and (…) he presents a lucid analysis of our capacity for perceiving time. He observes that we are always in the present, because the past is past and therefore does not exist, and the future has yet to arrive, so it does not exist either. And he asks himself how we can be aware of duration – or even be capable of evaluating it – if we are always only in a present which is, by definition, instantaneous. How can we come to know so clearly about the past, about time, if we are always in the present? Here and now, there is no past and no future. Where are they? Augustine concludes that they are within us:
It is within my mind, then, that I measure time. I must not allow my mind to insist that time is something objective. When I measure time, I am measuring something in the present of my mind. Either this is time, or I have no idea what time is.
(…)
Augustine’s exposition of the idea is quite beautiful. It is based on our experience of music. When we listen to a hymn, the meaning of a sound is given by the ones that come before and after it. Music can occur only in time, but if we are always in the present moment, how is it possible to hear it? It is possible, Augustine observes, because our consciousness is based on memory and on anticipation. A hymn, a song, is in some way present in our minds in a unified form, held together by something – by that which we take time to be. And hence this is what time is: it is entirely in the present, in our minds, as memory and as anticipation.
