I work at a youth center in the middle of a rapidly urbanizing small town in Eastern Morocco. One of the civic projects I started here is an environmental club. On Friday, we were cleaning up the grounds of the youth center, full of fallen trees, decades-old plastic, abandoned liquor bottles, shoes, and egg cartons. We unearthed a teapot, an umbrella, a toilet, and a 12-foot tall slide. Made out of steel and heavily rusted, the old equipment lay on its side, forlorn between small bushes and a pile of trash. I pointed it out to my friend Mohamed Jifjaf, who said he remembered when it was part of a playground, some twenty years earlier. He clearly recalled using it as a child. I asked him how do you say ‘slide’ in Moroccan Arabic. But he didn’t remember.
It should be noted that this was the first slide I have seen during the 22 months I’ve lived in this country. They are uncommon. So you can imagine the excitement he must have felt as a child, and you can picture the importance of that playground, in a place with few parks and no diversions outside of dirt-soccer. This thing played a significant role in his young life. Now it is rusted and its name is lost.
Although its basic skeleton remains, the slide is radically different from what it used to be. Can we say the same of Mo Jifjaf? It is a question I’ve been thinking about for the last few years.
An article recently came out in the online science magazine Nautilus titled “Why we procrastinate”. Building off the philosophical work of Derek Parfit, the piece explored recent neuroscience discoveries relating to how humans see themselves in the future. Parfit claimed that a child who begins to smoke, while knowing full well that a later version of him will potentially die young of cancer, does so because he considers his future self to be a stranger. Looking in the opposite direction, we’ve already broken our new year’s resolutions because they feel like somebody else’s promises. One of Parfit’s most memorable claims related to this line of inquiry is not mentioned in the article: he doesn’t need to worry about dying at some point in the future because, by the time he gets there, he’ll be somebody else.
Now for the neuroscience: The medial prefrontal cortex and the rostral anterior cingulated cortex show high levels of activity on brain scans when the subject is thinking about themselves. However, those areas show no activity when the subject thinks about himself or herself in the future, or when they think of a random third person. Other, specific areas in the brain show the same activity, when thinking about your future self and when thinking about another person.
Naturally, psychologists want to figure out ways to strengthen commitment to future selves. After all, it could be a powerful advertising and policy tool. Allianz, an insurance company, is currently showing state employees digitally manipulated pictures of their own aged faces immediately before the employees make decisions concerning pension allocations.
So the current Jifjaf and the childhood Jifjaf consider each other to be strangers. But is it just a trick of the mind? A psychologist’s sleight of hand? Or are they actually different people? Parfit’s answer is yes and no.
How do people persist through time? Put another way, what is a person? Am I, at the age of 24, fundamentally the same person I was as a child? Two competing theories have emerged in recent philosophy, underpinned by emerging neuroscience, quantum physics, and post Einstein-ian notions of time. People may perdure, or they may endure.
When a person perdures, he extends through both space and time in the same manner. Try to conceive of the lifecycle of an oak tree. Spatially, no two parts of the tree can occupy the same area; two separate leaves cannot exist in the exact same space. The trunk cannot be in the same place the roots are. Additionally, the roots are but a portion of the tree, as are the trunk and leaves. When an object perdures, its temporal extension is similar to its spatial properties. Each temporal stage, or instant in time, holds a corresponding portion of the tree that, when united, fill it out in its entirety. One temporal slice might hold the acorn, another might hold the sprout, another the full-grown tree, and another the decomposing matter of the organism. Just as each part of the tree is a portion that, when combined, unite to form the entire physical plant at a given instant, each temporal slice of the tree is merely a portion of the whole. Due to their extension across time, perduring objects are not present in their entirety at any given moment; instead, each moment holds its corresponding temporal slice of the object. Think of the self as thinly-sliced, 4-dimensional deli meat.
The other theory is the common-sense version (endurance). An object or person’s spatial and temporal aspects differ ontologically. That is, I am me, always. I exist in my entirety now; I am not a mere time-slice of my overall self. As another modern philosopher Velleman says, when something perdures, each temporal slice contains merely a portion of the whole, but for something to endure, it must be “wholly present at a single point in time”. Our basic ideas about people and objects states they are wholly present at the current moment. But, and here’s the kicker– persistence requires an object to be present in multiple moments in time. That is, we’re trying to talk about child Jifjaf and adult Jifjaf. We want them both to be Jifjaf, the whole Jifjaf. But if the entirety of an object is present at a single point in time, with no parts of it missing, then surely its various temporal parts cannot be simultaneously present- as those parts necessarily exist at different moments in time. So endurance is inherently contradictory. Or is it just a philosophical sleight-of-hand?
I don’t think so. The mind, in general, shows exceptional bias towards the present moment. We always believe that things of great consequence are occurring, a notion that is reinforced daily in the news. We want to create links, to categorize things together. When I remember myself as a child, I elide the two pronouns- my current “I” and my childhood “I”. We don’t possess the grammatical flexibility to make subject distinctions between current self and future self. We want to say I am me, was me, will still be me. We want to conceive of each subject of experience as entirely present at all its particular points in time. But at each of those times, we are merely pieces of a greater whole- some of them smaller, some bigger, some rusted, some uncorroded.
How much do people change over time? Well, they don’t change at all, because they extend through time, rather than move through it. But then again, they radically change, as each momental self has very little linking it to other bits of the self that occupy other past and future time slices. We all strive to connect things, to write narratives onto existence. After all, what makes me think an old abandoned slide and four-dimensional personhood have anything to do with each other?
Who are we? We only have a couple tools to build the notion of ourselves. We have habit, memory, and the urge in our brains to connect past with present with future. But according to the article in Nautilus, we aren’t even that good at doing it. Perhaps that’s a good thing.
It means that friends you’ve lost still exist, as your past time-slices intersected. Time has not lost. You are not rushing towards death, and when you get there, it won’t even be you anymore. At least, that’s what Parfit says. Unfortunately, I’m not sure how to explain it to Jifjaf in Oujdiya dialect.
 J. David Velleman, So It Goes, Amherst Lecture in Philosophy 11.iv.2006, 4.