This essay should discuss the question of what it is we talk about when we use the term “object.”
An object - a thing - is a completely natural concept to us. We see a stone. It is an object. We see a zebra, it is an object. Objects are things which occupy space and have some shape. A cloud is also an object. But a cloud is a gaseous, rather amorphous thing without clearly defined shape. More often than not you’ll see multiple clouds instead of just a single one. And they can break apart. Or they can merge. When they do, at what point exactly do two clouds become one? Similar questions: at what count does a small amount of grains of sand, when you add more grains to it, become a pile? When you look at any mountain, at which exact point does it end and at what point does the valley begin?
Think of what happens when you scratch yourself and shed a tiny piece of skin. Imagine you lose just one atom. Whereas before that atom belonged to you, now it doesn’t anymore. Consider the opposite. When put cream on your skin and your skin assimilates it, it becomes a part of you. The same goes for eating. The things you eat become part of you. When you breath in, oxygen taken in from the air becomes part of your bloodstream. During a year the majority of the atoms of your body are substituted with new ones and yet you remain you. That is, your identity still remains the same. There is an old philosophical thought experiment dedicated to this idea. It is called the Ship of Theseus. To repair it after a journey on sea, you exchange some part of it. Over the years, you replace every part of it, and yet we can say it remains the same ship? Let’s twist this a bit and assume there are two similar yet differently looking ships. When we replace parts, we make it gradually take on the shape of the other ship, until eventually it looks completely like the other one. What do we make of that?
Another famous philosophical example: a river. Every moment the water in it flows. It gets replenished from the fountain and merges with the ocean at its mouth, or loses water through heat dissipation. Is it always the same river? And what is the river? Is it the water? Or the shape holding the water? What if water stopped flowing in it for good? At what point (of erosion) does it cease being a river?
Here’s a funny one. How would you think of teleportation? I mean in the case where a (for example living) thing gets re-assembled at another point in space, by transmitting just information. The matter is taken from the surroundings of the target location and it will yield a thing, but will it be the same thing? What about replication (similar, but the original thing does not get destroyed)?
What I am getting at here is that it is a bit of a mystery of what the actual “rules” are that a) make a thing a thing b) identify a changing thing as the same thing. In this text I want to focus mostly on a. But a short comment on b is in order here. It is quite interesting to learn about how that works from a cognitive development perspective. It seems to be a non-trivial feat for children to first of all understand that an object that vanishes from view because it is occluded for a short period of time does not actually vanish. And then, how does the child actually track an individual object through time. How does the child recognize the same thing after some time has passed? And how does it do it, given that the thing undergoes changes (as indicated)? Now back to a.
We tend to take for granted that objects are simply there, ready for us to recognize them. We think they have an existence totally independent from us. Stated differently, we think that that they exist is the cause for us to be able to recognize them as such. If this were so straightforward, though, everyone would recognize the exact same objects as objects. That is, when we add another grain of sand, we all should agree when exactly the collection of grains actually becomes a pile. We should be able to come up with a rule that exactly tells us how to pick a collection of atoms from a “background” of other atoms such that we can call it an object. Unfortunately, nobody has ever come up with such a rule.
That is were the idea of reductionism comes in. Since we can’t tell what objects are, I mean the ones visible to us, we break them down further and further into smaller and smaller parts, until we find the smallest units. Instead of looking at the pile of sand or asking where the mountain begins, we focus on a grain of sand and then imagine crushing it so that we can look at ever smaller grains of sand. Right there when we can’t break them down any further, we’ve reached the level of atoms. ‘Atom’ literally means indivisible. Now the problem is: we know that they are not really indivisible, for atoms themselves consist of smaller parts. In one particular model of what we think (or thought) an atom is, these particles buzz and fly around the core of the atom, which itself consists of particles. When atoms bond, that is when they stick to each other to form molecules, it is because they share some of those smaller particles. That means one particle belongs to two atoms. According to our desire to find an unambiguous rule that tells us what constitutes an object we must insist now that only the smaller particles have a real existence as objects. But, you see, sadly we are not so sure about what those particles exactly are either. You may have heard that there are descriptions of particles as waves. This all is utterly confusing. I think the least thing we’d hoped for was to find some thing that is extended in space. But it is not clear at all if this assumption of ours is warranted by reality at all.
It seems like the problem with the aforementioned question of atoms is that we started with an idealization. We started with the assumption that there must exist a smallest thing. But note how what we require from this smallest thing is exactly what we think makes an object, namely that it has a spatial extension. The small difference between an idealized atom (in the sense of smallest thing) and an object is this: whereas we imagine objects as having a shape (in addition to spatial extension), in the case of atoms that does not interest us. We might simply imagine them as spheres (the ‘perfect’ shape, clearly an idealization).
They key to understand what is going on is to invert our perspective and say that objects are not properties of the natural world but rather of the mind. Instead of detecting an object, we ‘see’ it into the world. We do that by “drawing a boundary” around a cluster of material. In a sophisticated pattern-recognition process we separate out some material from a background of material and call it an object. What we recognize as an object does not have to be one individual (this also means ‘indivisible’) thing. When ten thousand mosquitoes buzz around or we see a big swarm of birds, in each case we kind of see them as one object, like we see some arrangements of gases as clouds - that is, also as objects. It is in exactly the same way that we see a stone as one object. We came up with the idea of an atom (a smallest thing) precisely because we can see objects and can imagine breaking them down into smaller things. At whatever level, we see bounded entities, and when they become smaller and smaller, shape does play less and less a role, which is why we default (in our imagination) to spheres. That’s also where the billiard ball model of physics comes from, if you know what I mean. We just can’t help seeing it that way.
To be sure, this is no arbitrary process. We pick stone-like things out from a background of non-stone things. We might not do infallibly so, but when we don’t recognize something correctly, we typically got deceived by our senses. Under good light conditions, however, and if nobody tricks us, we often converge pretty predictably to recognize the same things, especially if they are living things or rocks thrown at us. When we recognize different things, let’s say both of us disagree slightly over when the grains of sand became a pile, or when exactly the two clouds became one, or where exactly the mountain starts, this is rather inconsequential. All in all, although different minds process patterns to recognize objects individually, there is not much (what we would call) subjectivity involved (in subsequent posts I’ll go more into how expectations and pre-conceptions shape what we see). While this means that there are no objects out there in reality, this does not exactly mean that we make them up, either. Objects are just properties of functioning minds. For any but the least complex living beings it is simply not imaginable to see the world in any other way, to see the world not split up into different objects. All of this is not to say that there is a primacy of consciousness over reality or that we create reality. It is only to say that objects are more a part of us than they are an intrinsic part of the world. Or better: they are products of both our minds and the world.
Objects are the tokens in our little game of prediction of what happens next, which we play from moment to moment. What drives which objects are recognized - which boundaries we draw - is relevance, from the perspective of living organisms striving for survival. When birds move together as a flock, it makes sense for us to see the whole aggregate as one, instead of seeing individuals (the same goes for clouds consisting of gas particles). While we kind of still see the different birds, we certainly can’t track them individually (think of the shell game). We are interested in their behaviour as a flock. For us humans stones are relevant objects (we can hit our foot). In contrast, stones or mountains are not exactly relevant entities from the perspective of microbes. They certainly don’t exist as objects for them. In that light it is rather interesting that we can perceive galaxies (through telescopes) and atoms (through electron microscopes). But that’s a whole different topic. Let’s leave that for another day.