Compositionality

The everyday objects around us are assembled out of various other objects. For example an automobile is built out of a chassis, an engine, a body, etc. If we think carefully about this situation, we will run into a variety of puzzles and paradoxes. What is the value of reflecting on such difficulties?

Our habitual way of thinking about the world is to conceive of it as a collection of various objects, which relate to each other and to ourselves. We try to arrange the situation with ourselves relating in some stable way among the various objects. Somehow though problems are constantly arising, and when we are not somewhat desparately trying to patch things up to return to some manageable level of stability, we are worrying about where and when the next outbreak of unwelcome surprises will come and how can we be prepared to respond.

So it really does seem counterproductive to go looking for trouble. Life is difficult enough already without anyone trying to topple over nice cozy arrangements such as automobiles whose engines are so neatly bolted to their chassis. Is the object of such an exercise to prod us into yet another weekend repair chore, hunting down the aisles of hardware stores looking for yet stronger glue to secure our lives from these latest assaults? Let's just lay back and drink lemonade instead and forget the whole exercise.

The goals of Buddhist practise and of ordinary behavior are not different. Beings just want to be happy, and perform what seems to them the most effective actions to become and stay happy. Despite such universal intentions, the world seems quite filled with suffering. Despite everone's cultivation of happiness, unhappiness prevails. The Buddhist diagnosis of this situation is quite simple: the vast majority of beings are confused about what sorts of actions have what sorts of effects. The actions they perform, in order to secure happiness, actually generate unhappiness.

The Buddhist path is a training in methods that truly produce happy results. Part of this training is to cultivate an understanding of the ways that common confused approaches lead instead to suffering. One needs to understand what is confused about confusion. A classic instance of confused action is rigidly clinging to a conceptualization of the world as some particular arrangement of objects with various relationships to each other and oneself. If one can see that any such conceptualization is of only limited validity, that the more rigidly one clings to such fixed ideas the more pain results from the inevitable mismatches, then one may become more able to catch oneself as one's habits again drive one into such conceptual clinging, and gradually train oneself to develop a mental pliability that can freely take up and let go of conceptualizations, with the openness to allow the value and use of each to display themselves.

The paradoxes considered here are not new. Various versions appear in the classical philosophical traditions around the world. Any way of thinking has somehow to make peace with these paradoxes. Whatever solution is settled upon is inevitably unstable, but various defense mechanisms can be cultivated to prevent the logical problems from destabilizing the patterns of thinking that form one of the fundamental subsystems of any culture. Modern scientific culture has its instabilities and defense mechanisms like any other. By bringing these to light and recognizing them we may become more able to weigh their costs and benefits and choose among alternatives more wisely and compassionately.

So let's look at some object like an automobile. Perhaps this automobile is connected to a trailer. Does this combination of automobile and trailer form some new object, an automobile-plus-trailer? Of course this is just a game of semantics, of words and their meanings. But if it is just a game of semantics to ask, "Is that an automobile-plus-trailer," isn't is just as much a game to ask, "Is that an automobile?" Just like "automobile-plus-trailer" is just a made-up word one can use to refer to an arrangement of an automobile connected to a trailer, isn't "automobile" just a made-up word one can use to refer to an arrangment of a body mounted on a chassis with an engine bolted in and hooked to the wheels? Suppose you put an automobile in your garage, and then pull the engine out and set it alongside. Is there still an automobile in the garage? Is the engine still part of the automobile or are the automobile and the engine now separate objects? Suppose you mount the engine in some other chassis-plus-body and drive that new combination away. Is the chassis-plus-body still in the garage an automobile? Does is still include the engine that was driven away? Suppose we mount a new replacement engine in the chassis-plus-body in the garage. Is there now an automobile in the garage, and is this new engine a part of it? Is this automobile the same automobile that we started with in the garage?

In case this all seems totally absurd, you might consider the problems that arise with car theives, chop shops, and serial numbers. The black market thrives on ambiguity and instability!

Here is another puzzle. Suppose we define a place-setting to be a knife, a fork, and a spoon. Suppose we have a drawer containing four knives, four forks, and four spoons. How many place-settings are in the drawer? The easy answer is four, but wouldn't it be truer to say 64? Label the knives K1, K2, K3, and K4, the forks F1, F2, etc. Wouldn't it be accurate to say that place-setting K1+F1+S1 is a different place-setting than K1+F1+S2?

Reductionism

The more one considers how it happens that some arrangements of smaller objects somehow form a larger composite object whereas different arrangements form different larger objects or no larger objects at all, the more one tries to understand just how those larger objects come into existence or pass out of existence, the more one is driven to the conclusion that these larger composite objects are not really existing things that suddenly spring into being or vanish as the smaller objects are rearranged. Instead it starts to get clearer that we think about and talk about these larger objects as a sort of shorthand summary of lots of details concerning the smaller objects and their arrangement, details that don't matter much anyway. So if someone asks, "Is there an automobile in your garage?" the most accurate reply might be something like, "There is an arrangement of pistons and shock absorbers and metal panels and lots of other things, arranged in such a way that you can climb in and drive it around, and it strongly resembles in shape and substance other arrangements which people generally call 'automobile', so using that commonplace shorthand way of speaking, yes, there is an automobile in my garage." Of course such accuracy is mostly a waste of time.

But such accuracy is not entirely a waste of time. If everyone understands what is behind a statement like, "Yes, there is an automobile in my garage," then perhaps no one will be upset when the situation is actually a little bit over into the grey area, so perhaps the automobile is not is the best repair, perhaps some not quite essential component is missing, so when one person's expectations are disappointed there is mutual understanding that words can never capture reality so such disappointment is not entirely avoidable and need not be blamed on anyone, so anger and a cycle of retribution need not be triggered.

If large composite objects like automobiles "exist" merely as a conventional shorthand way to summarize in a rough way some arrangement of smaller objects, what about those smaller objects? Do they also exist in such a merely conventional fashion? When your sunglasses fall out of your pocket as you cross the street and somebody's Ford Expedition smashes them into pieces, maybe that's just a shorthand way of saying 6000 pounds of steel, but such a real effect surely has some similarly real cause!

The modern scientific answer to this puzzle is reductionism: while automobiles and engines and pistons are just conventional names to summarize arrangments of smaller objects, at some point there is an end to this process of examining objects to discover how they are composed of smaller objects. A piston is composed of a huge number of atoms, and the atoms themelves can be broken down further into elementary particles such as electrons. An electron is not composed of smaller particles, it just exists all by itself as just what it is, an electron. The real true description of the world is that it is some evolving arrangement of elementary particles. Of course this arrangement involves a mind-boggling mass of details, so inevitably we have to talk about it with conventional shorthand terms, but those terms don't refer to actually existing objects, merely to loosely defined arrangements of elementary particles. This is the reductionist view of modern science.

This reductionist view actually started to fall apart just as it appear to finally have matured. Of Albert Einstein's famous three papers of 1905, the paper on Brownian motion established the actual existence of atoms, while the paper on the photoelectric effect gave a powerful boost to the nascent quantum mechanics that undermined the foundations of that existence. But the reductionist view runs into problems even before we run into quantum mechanics.

Suppose the classical mechanical reductionist view were somehow correct. Suppose we somehow managed to construct a perfect description of the world. This description, according to the classical reductionist view, would consist of a list of particles and their coordinates. Perhaps the description would even have the complete history of each particle, the sequence of values of the coordinates as they evolved and will evolve over time. This description being quite vast, we store it in a sophisticated high-powered computer database. But there are some tough design problems in the way of constructing this database. The database will just contain a set of records, something like

particle identification number time x location y location z location
151900166 874999.30567 2803486.55483 -73384.59446 1036438658.22953
151900167 874999.30567 -1304857504.583299 205333.6895 142726658304.789433

The immediate problem is: what measurement units and frame of reference should be used in the perfect description? If I wanted to see where that Ford Expedition drove off to, I could just find the coordinate for where your sunglasses where when they got smashed, find what particle was just above that point a few inches, then jump ahead a couple of hours and look up where that particle is now. But how can I find the coordinate where your sunglasses got smashed? If I knew the label for one of the particles of your sunglasses, maybe I could look up its location when they got smashed. Of course, that particle has a very long history, perhaps billions of years, so there is still the problem of knowing what time they got smashed.

So there is the first problem with the reductionist view of the world. A description that consisted merely of particles and coordinates would be quite useless. The only reality we know is the conventional reality, including especially our own self. If one searched our perfect reductionist database for any configuration of particles fitting the description of "Ford Expedition smashing sunglasses", there might be hundreds of matches. Some of these matches might even be on different planets, on different galaxies, millions of years in the future. I want to know about the events that are related to me, not to some similar arrangement of particles very distant. To be useful, the database will have to somehow include the relationship of the particles or coordinates to the user's experience in conventional terms. Thus a perfect description must include conventional terms. These conventional terms are essential to the description. The reductionist view of the world is incomplete in an essential way.

The reductionist view proposes the ultimate absolute existence of elementary particles and the nonexistence of composite objects. We have seen that composite objects are essentially required in any adequate description of the world, so one plank in the reductionist platform is flawed. The classical Mahayana Buddhist philosopher Nagarjuna had already pointed out the flaw in the other plank, the existence of elementary particles. The flowering of quantum mechanics in this century has revealed much more complex phenomena underlying the appearance of elementary particles. Nagarjuna simply pointed out that if such particles existed they would have to have occupy some non-zero extent of space if things weren't to just collapse in on itself, and any such non-zero extent is necessarily composite, being divisible into smaller non-zero extents. With quantum mechanics, things not collapsing on themselves is explained by Fermi-Dirac particle interchange anti-symmetry. But such anti-symmetry undermines the existence of elementary particles every bit as much as a non-zero extent would have. What really exists from a quantum theory perspective is something like a collection of elementary particle fields. The fields are what exist, the particles are just the appearance of the field.

But actually things are quite a bit thicker that this. The various particle fields are interacting. The particles we observe are actually bundles of interacting particles. If we try to peel apart these bundles, we find that the peeling apart process never ends. This rude discovery was called the ultraviolet catastrophe. Renormalization group theory was invented by Feynman, Schwinger, and Tomonaga to compute appearances despite the nonexistence of the bare particles.

So quantum mechanics has really given up on the existence of elementary particles. The particles we observe can be analysed as excitations of coupled fields, but those fields only exist as those appearances. The various modes of excitations of these fields change depending on the situation. The elementary particles that exist inside crystals are quite different from those that exist in a vaccuum. For example, sound waves do not exist in a vaccuum, but do exist in crystals. Sound waves are excitations of the crystals, and these excitations are quantized, which is to say appear as collections of elementary particles, known as phonons. Solid state physicists measure properties of phonons and use them to predict the behavior of crystals. Thus these particles are quite real in the sense of having clearly observable impact on human experience. Yet they exist only in the context of a cystal, not in a vaccuum.

Even more curiously, phonons and electrons interact. Thus, in a crystal, any excitation is really a combination of phonon field and electron field in coupled oscillation. Generally the phonon or the electron aspect dominates, so the excitation can be labelled "phonon" or "electron". But at some frequencies there is a sort of mutual resonance, where the phonon and electron field are working tightly together. In this case the excitation is called an "exciton". As the frequency shifts, the modes of excitation of the fields that compose the crystal shift smoothly from being phonon dominated to a balance and then to electron dominated. The particles that appear vary smoothly from phonons through excitons to electrons.

I certainly don't mean to hold up any particular physics theory as being correct or incorrect. I bring up the complexities of quantum mechanics merely to point out that, just as the reductionist view understates the existence of composite objects, it also overstates the existence of elementary particles. The conventional view, that objects like automobiles just simply exist as they appear, very quickly runs into trouble as their behavior reveals their composite nature. But as we try to pin down just what objects really do exist, we find the project to be quite difficult. The closer we look, the more complex the underlying phenomena appear.


This page hosted by
Get your own Free Home Page