A recent viewing of "Donnie Darko" put me in a musing mood, and I spent most of my driving time today pondering the concepts of determinism and free will. I won't spoil it, but there's a scene where Donnie is discussing these concepts with a science teacher, and makes a scaled-down argument of my post (that essentially if a god exists outside of time, even if he/it chooses to give us free will, the constraints of the *system* prevent us from actually making choices that affect how our futures will unfold). Determinism is a philosophy that holds that the Universe is mechanistic and "fixed," that is, the initial starting conditions of the Universe dictate how every event at every point in time will occur. If this is true then, as Laplace pointed out, if one knew the exact starting conditions precisely enough, and understood the governing laws well enough, one could build a model (or an insanely powerful computer) that would predict the future with complete accuracy because all events are the results of previous causes, and in turn are the causes of future events. From that standpoint, free will is an illusion. We *perceive* that we have free will only because we travel only one direction in time and cannot see the future. Because of the starting conditions of the Universe, I was always going to write this entry, complete with all the rewriting and editing, and I could not have prevented myself from doing it. If one were able to "rewind" time a week and then let it play out again, I would make the exact same choices that I've already made, even though on the second "playing" I would still perceive them as my free choices.

One chapter in a book on physics I once read has stuck with me. It describes how an observer outside our Universe (or more particularly, outside our spatial and time dimensions) would see us, and it's always been a hauntingly beautiful visual for me. We're all familiar with our three primary dimensions (length, width, height) and we tack on the fourth dimension of time to represent *when* that three-dimensional object exists, but as three-dimensional beings we (with the possible exception of the extremely creative and the insane) aren't capable of visualizing four-dimensional objects. But to illustrate it in three-dimensional terms that we can understand, imagine that instead of three physical dimensions we only had two (say, a piece of paper, ignoring its thickness). On this sheet of paper, draw a circle. This circle has two dimensions, and now add the third dimension of time. In this example, the three-dimensional image of the circle is an object composed of every single place that circle occupies as it moves forward in time. So, for example, if you spin the paper, the circle becomes a sphere. If you move the paper forward, the circle becomes a cylinder. If you move the paper in a random pattern in the air, the circle becomes a snake-like form that has, as its cross-section at any point in time, the circle. Extrapolating out to the larger world, imagine our sun. Its four-dimensional form would be a somewhat wandering yellow line that lazily circles the center of our galaxy (and smudges slightly as our galaxy moves away from other galaxies), and of course at any point in time its "cross-section" would be a nuclear sphere. Our planet, then is a smaller blue line that circles the yellow line in a helix pattern (along with the lines of all the other planets that orbit our sun, each at different speeds and angles), and our individual four-dimensional forms are even smaller lines that make random, jumping patterns on the surface of the blue line. Taken altogether, the timelines of all the particles in the Universe form "the pattern," a static object that represents the entirety of the Universe for its complete existence, which to me is a beautifully complex image that boggles the mind.

Here's the trick that ties this to determinism. We exist within time, but time is more than a dimension. It can be warped and altered, and different points experience time pass at different rates. Our biology wouldn't allow us to exist outside of time, but if one *could* step outside of time (and our notions of past/present/future) and become an observer of the entire Universe, and in effect "see the pattern" (i.e., the Universe as a static four-dimensional web of lines), one would know, or could learn, the predetermined paths of everything. From a perspective outside of time, there is no "now"; all points in time are equally valid (and thus to a point on the pattern billions of years from our "now" all of our "future" is its "past" and unchangeable). If you were to look at the small timeline of a human, you would see his entire existence as a single static object; his birth, choices and death would all be visible in one glance, and even though *he* would think he was deciding to buy a soda instead of a cup of coffee on a Tuesday, you would know the moment you looked at his timeline that he did, does and will make that decision, and had no choice but to make that decision. Even the possibilities of time travel wouldn't alter the pattern, because the timeline is an unchanging physical object that simply "is." An observer *within* the time dimension who could see the pattern might appear (to himself) to be able to make changes (knowing today that I'm going to buy a soda next week might allow me to decide not to buy it), but from the outside observer's perspective, that "alternate" choice was actually the choice I was originally going to make; I had no free will, and the "pattern" I saw was not the true pattern (or, if it was the true pattern, I would know what was going to happen but be unable to alter it; everything would unfold the way I knew it would, regardless of my wishes). The outside observer would know from my timeline that I was always not going to buy the soda, and only fooled myself into thinking I'd made a change in the timeline because I erroneously thought I *was* going to buy it. I'm like a character in a movie, who will repeat the same actions no matter how many times the DVD is replayed.

Do I subscribe to determinism? I don't know. It's still an ongoing, unsettled debate in philosophy, but the advent of quantum mechanics (which has, apparently, true randomness, up to 11 dimensions instead of 4 and particles existing in terms of probabilities until observed) has at least given nondeterminism some solid ground. The origin of consciousness and the concepts of emergent properties also factor in heavily, but that's a blog post of its own. If I were to choose a side, it would just be because I like it more, not because I have any evidence that it's right, so I'm, if not ambivalent, at least undecided. If determinism is true, that's the only choice I can make anyway. On the other hand, as long as *I* perceive it as free will, from my framework it doesn't really make much difference. The illusion is complete.

Posted at 2:55 AM.  |     |   Permalink to this post.