I hope this isn’t too late. There are actually two flaws in the argument, one of which conceals the other.
The first flaw is that your fully determined universe assumes complete information. The only way that you can know that your universe is fully determined is if you occupy a “god’s eye” point of view in which you can see the trajectory of every wave and particle in the universe from the very beginning to the very end, all at once in an ever-present now. And not only do you see your own universe splayed out across time, but you see an infinite number of parallel universes which enumerate all possible decisions at all possible decision points from all possible points of view. In other words, you are standing outside of what mathematicians call Hilbert space, looking in at the cosmos from outside.
Since you are looking at the four dimensions all at once, the cosmos appears static (and mind-bogglingly huge). However, once you assume a point of view, you not only choose a location in the three spacial dimensions, but you become situated in time. This enables you to perceive motion and change relative to the other three dimensions, so in this respect, assuming a point of view places you inside the cosmos. Assuming a point of view imposes specific limits on the completeness of your information, and this incompleteness is what creates the subjective sense of indeterminacy in a fully determined universe.
Now you might be thinking, “If I had a snapshot of the universe, I could extrapolate the position of every wave and particle from the Big Bang forward.” but in principle you can not. The reason is that you have chaos even in the fully determined universe (you can call it chaotic determinism), which is sensitive to initial conditions. The mere act of choosing a viewpoint seeds the system with a random variable that defeats any attempt at meaningful prediction, except in the very short run.
Its as if you went from standing above a billiard table where you could see all possible games unfolding before your eyes, to the viewpoint of a single ball in a single game. When you assume a point of view, you are necessarily limited as to what you can see. The past is fully known and determined while the future remains unknown and indeterminate. So the first flaw in the argument is that it doesn’t allow for a point of view—which is, to say the least, the very cornerstone of our consciousness, and a necessary condition.
The second flaw is that the variables we take into account in making decisions are “emergent”—which is to say, that even though consciousness appears to subjectively center on the individual, and therefore reducible to the physical processes of the brain, what one experiences as consciousness is not the brain itself but the computational space created by the brain. For example, an electronic calculator may only have a certain number of integers and a certain number of arithmetical operators whose permutations comprise a huge computational space.
The brain is a massively parallel analog computer which creates a “mind’s eye,” holographic memory, linguistic sign and symbol definitions in its own kind of computational space. One could define consciousness as a kind of “decision space” in which information accumulates weight, meaning, and salience until there is enough of it to reach a tipping point, at which time the individual makes a decision which triggers a cascade of electrical, chemical and physical events, causing the individual to do something different than he was doing before. In this respect, the decisions being decided in decision space are driven by collective, cultural, “hive-like” processes—e.g. price information, social gaming strategies like the prisoner’s dilemma, symbolic interaction, memes, etc.
Think of decision space as the individual surfing on a cascade of information, making minor adjustments to keep himself from wiping out. Information accumulates to solve a number of smaller problems which, in turn, are “chunked” into solutions to larger problems. The more information the individual has, the more of a “no-brainer” these decisions become. But, where one must make decisions based on incomplete information, one must exert effort in order to decide. That effort may take the form of seeking additional information, or calling the decision based on some heuristic or algorithm. In any case, that exertion is what we commonly regard as “free will.”
Typically, we apply “free will” to decision tasks that involve competing moral outcomes, such as the decision to be selfish or to be altruistic in any given instance. These may seem like individual decisions, but in the aggregate, they determine the content of culture and the course of cultural evolution. In this respect, individual decisions are shaped by informational cascades that create things like zeitgeists, “ideas whose time has come,” and historical events.
So, if you allow the observer to have a point of view, you have a subjective consciousness that can be organized in such a way as to solve problems. And the effort necessary to overcome the indeterminacy of these decision tasks, can meaningfully be called “free will” even in a fully deterministic cosmos.
See also:
Ian Stewart
David Deutch