The Philosophy of Relativity
I should have posted this a while ago... but here we go. I wrote a paper on the implications of the theory of special relativity on free will. Some people were asking, either out of real interest or to be polite (I don't really care which :), to read it, so there it is.
The PDF looks kinda weird sometimes for some reason; a bunch of letters are smushed together. I dunno what caused this, but apparently open office's PDF exporter could use some work. It prints fine... anyway sorry 'bout that.
Last semester I took an introductory course in the philosophy of science. I don't think it would have been too exciting aside from the fact that my prof, Dr. Vesselin Petkov, has PhDs in both philosophy and physics and has recently written a book on the "nature of spacetime". I've been reading books on "popular physics" by people like Stephen Hawking, John Gribbon, Michio Kaku, and the like since high school, and, while I won't claim to have thoroughly understood them, I was amazed at how incredibly weird our universe is at the extremes. Over the last few years, I've been pleased to see that this weirdness isn't confined to physics—and that's probably why I've decided to study philosophy for a while.
Our professor decided to dedicate about a month to the study of the philosophical ramifications of the theory of relativity. I think this was a bit of a controversial choice, since many students were expecting just a survey, discussing "real" philosphical issues like realism vs. antirealism, reductionism, the scientific method, scientific revolutions, etc. But it was a bold move on the professor's part, since from what he said and what I can tell, these ideas are regularly discussed in academic circles, despite the fact that the theory of relativity is over 100 years old now. So maybe we sacrificed depth on other topics for a real taste of what philosopher of science talk about these days.
In fact, next year is the 100-year anniversary of the talk Hermann Minkowsi, one of Einstein's teachers, gave in which he explained his idea of the 4-dimensional model of the universe. It was a pretty radical model, in which he claimed that time is a complete dimension, much the same way that length, width, and height form the spatial dimensions with which we are all familiar. The most intriguing part is that Minkowsi believed that this model represented reality; it wasn't merely a mathematical tool. In fact, he believed it was the 3-dimensional model that was the tool, that it didn't accurately represent the universe (or the "world" as he called it).
The argument rests on the fact that simultaneity is relative, that is, observers at different relative motions will have different set of simultaneous events. If you're moving very quickly towards me, and I see two nearby stars go super nova instantaneously, you might see one explode before the other. If you take the instant of time at which we are immediately side-by-side as we pass each other, the objects that simultaneously exist for us will be at different times. For you, the star right now might be as it was for me two seconds ago. I'm deliberately not saying "see", since the speed of light introduces further complications, but if you "freeze" the universe at a time common for both of us, the universe that is frozen for you will be different from the universe that is frozen for me.
The only way to explain this without introducing complete relativization of existence is to introduce an extra dimension. With a time as a dimension, special relativity "clicks" into place. An object extends into the temporal dimension, and I see a different three-dimensional "slice" [1] of the universe than you do, so objects are at different times in their lives for me and for you. In fact, the four-dimensional figuration neatly explains two other consequences of relativity—time dilation and length contraction—but I won't go into that right now.
On the surface, it doesn't really seem that weird to treat time as a dimension. When we arrange a meeting with someone, we normally specify a time coordinate along with spatial coordinates (corner of Guy and Ste-Catherine, 2nd floor, 12:00 pm). But if time is a complete dimension in the geometric sense, then it must be that the entire dimension exists, not just a point on it. In other words, when you look at a table, you see its entire height, its entire width, and its entire length. By extension, at one point in time the entire height, width, and length of the universe must exist (although weird things might happen far out there, but for all intents and purposes the universe has height, length, and breadth). Thus, the entire time of the universe, including everything in it, exists as much as its spatial dimensions do. The past and future of the universe exist in the same way that the present does; they have the same ontological status.
Well that's a pretty damn strange concept when you look at it for more than a second... the most obvious question being "why does it feel like time is passing then?" The only answer that anyone has been able to come up with is Hermann Weyl's idea that our consciousness "travels" up our world tube (the 4-dimensional representation of an object), perceiving a succession of 3-dimensional "slices". This is a pretty unsatisfactory answer for a number of reasons, but it stems from the fact that we need something to explain the disagreement between the theory and experience. Bear in mind that the theory of relativity has been experimentally confirmed many, many times; Prof. Petkov has even gone so far as to say it is the most tested of contemporary theories, given that GPS systems employ relativistic calculations constantly.
The question that really got me was pretty philosophical, something that I wouldn't have thought I would ever find particularly interesting—free will. If the future is already set, how can my actions and choices have any meaning at all? In some senses, it feels like a silly pedantic argument, the kind I would have scoffed at a few years ago... but I think back to when I found out that the church I attended as a child had predestination as one of its tenets. Even as a kid, this idea disturbed me... it didn't seem right that God would have put us on this planet and then determined in advance what I was going to do with my life. Moral responsibility requires free will in my mind. But after giving up Christianity when I was older and its concept of a god, I could breathe a bit easier.
It seems that, somewhat ironically, science has discovered that the old theological debate of predestination is once again valid. Interesting that at least we have something to fall back on... but while doing research for my paper I found the compatibilist approach (i.e. that free will and determinism are compatible) to be really... unconvincing, especially compared to the arguments that the incompatibilists had. So I wasn't getting much help there in fitting free will into a Block Universe.
I thought that perhaps quantum mechanics, with its ideas of probability (at least in the Copenhagen interpretation), might help out a bit here... and some people, like McGill professor Storrs McCall, have expounded a view, incorporating relativity, of a branching universe in which there are many, many possible futures, but only one becomes real. But the inverse of determinism, complete indeterminism, doesn't fare much better on the free-will front: a completely probabilistic universe doesn't give us any control over our actions either.
It was at this time that I starting noticing that the compatibilism/incompatibilism debate was mostly, if not entirely, over a certain type of determinism: causal determinism. This is the view that there's one single unbroken chain (or maybe tree) of causality, that goes back either infinitely or to a certain prime cause. But the theory of relativity itself doesn't imply anything about causality--one can imagine a Block Universe in which events were not linked causally in any way whatsoever. I guess you could say that the structure of the universe doesn't imply its content.
So in the end the only conclusion I could come up with is that free will isn't directly contradicted by the theory of special relativity, although if free will does exist it must be something rather strange, some ability for our consciousness to affect the world in an atemporal way. It's pretty odd, but then again the role of consciousness hasn't been very well defined in so far as it relates to a temporal dimension.
It seems, from a scientific perspective, that the real debate about free will really centres around biological reductionism. If our entire being can be reduced to physics and a (albeit hypercomplex) set of equations, then what we take as free choice might be just an illusion concocted for some reason by evolution, and our "decisions" are in fact just as deterministic as where a pool ball will go after being hit by another. The only way around it is to imply that we somehow cause effects that have no cause other than our will. Certain people call this "immanent causation", meaning the causation is immanent in us (in our consciousness or soul or will or something). If this is true, though, then what level of immanent causation do animals have? Unless there's a "big leap", which seems pretty rare in nature, animals must have some sort of free will, at least to some extent. But where does it end? Maybe then plants have a lesser but definite free will. What about inorganic structures? Unless there is some sort of gestalt that exceeds the sum of its parts and produces the ability to make conscious decisions, it seems that the only option is some sort of panpsychism, in which free will is present to some degree, greater or lesser, in pretty much everything in the universe. Weird.
None of these ideas are new of course, but one of the fascinating things in philosophy is how, when you take what appears to be a fairly straightforward idea, what appears intuitive to us, and really think about what it's saying and its implications and see what it really means, some weird weird stuff comes out. It truly amazes me how strange everything is when you peek below the surface.
1 Actually, due to the fact that the speed of light is finite, the "slice" we can see is in fact described by a 3-dimensional cone (a "light cone"), but the notion of a slice is close enough.
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cloquewerk) wrote,
thoughtful
