A deterministic system is one where changes to the state of the system are governed by a set of rules. The system’s state at a future time can be predicted with 100% accuracy if the current state of the system is known. Most every day physical systems appear deterministic to us – if you put a box of microwave burritos in the freezer, those burritos will stay inside the freezer.
A lot of people believe that determinism prevents free will – if an object’s behavior is totally governed by specific rules, then that object cannot have free will. You could claim that the burrito ‘chose’ to stay inside the freezer, but this would be akin to saying that a man tripped and ‘choose’ to fall to the ground instead of hovering in mid air before righting himself. (Which reminds me – I hate when I do something inadvertently, such as stub my toe, and someone asks ‘why did you do that?’ as if It were something I thought would be a good idea. Really gets me mad.) Our bodies are physical things. We know that physical things are subject to the laws of physics – wouldn’t this mean that our bodies (including our brians) are deterministic, and therefore we cant’ have free will?
Actually, the answer is ‘No, not quite.’ According to the experimentally verified and widely accepted (among scientists, anyhow) quantum mechanical model of the world, the behavior of physical things is nondeterministic. Over a given time period, an object’s energy fluctuates. The magnitude of these fluctuations is inversely proportional to the time period over which the object is observed. Over a very, very short time period, the burritos could get enough energy to ‘tunnel’ through the freezer walls and end up outside of the freezer, without anyone opening the lid to get them out. The probability of this happening, howerver, is extremely low. The indeterminancy introduced into the world provides a possible explanation for free will.
In our burrito example, If we look at the freezer for a long time, and eventually the burrito just appears outside the freezer, we could maybe conclude that the burrito ‘chose’ to come out of the freezer. Before, choice was impossible because we could tell to which state the burrito would transition. The addition of indeterminacy to the world appears to make free will possible. At this point you may be confused if you do not have a good understanding of computational automata, so allow me to explain them here.
An automata system consists of several states, several possible events, and a ‘transition’ function. An automata exists in one state at a time, and as events occur, the automata may change to a different state depending on the type of event that occured. For example, in the deterministic model of the burrito, there are two states:
1) The Burrito is inside the freezer
2) The Burrito is outside the freezer
Likewise, there are two possible events:
A) Nobody does anything
B) Someone comes along to change things up
If the burrito is in state 1) and event A) occurs, nothing happens – the burrito remains in state 1). If the burrito is in state 1) and event B) occurs, then the burrito will change to state 2). While in state 2), the burrito does nothing in the case of event A), and goes to state 1) (back in the freezer) if event B) occurs.
Adding indeterminacy to our system simply adds a third state:
3) The Burrito exists in a superposition of being both inside and outside the freezer
When the burrito is in any of the states and A) happens, it will transition to state 3).
The ’superposition’ buisness is true of the way quantum mechanics works in our world as well – an electron can have a superposition of multiple states. When it’s observed, howerver, the electron will collapse into one state; this collapse is a random event and the probabilty for collpase into a given state is based upon the amplitude of that state in the current wave function of the electron. In more simple language, the burrito could be 50% inside the fridge and 50% outside; when someone comes to look at it, it will ‘choose’ one of the states into which to collapse, with both of them being equally likely. Or, it could be 80% inside the fridge and 20% outside, in which case the burrito will most likely be inside the fridge if we check.
I shoud warn you that my undersatnding of quantum mechanics is rather poor at this stage in my life, and that although I’m sure what I’ve written is accurate, I can’t provide the depth of analysis that I would like.
The world itself could be a simply automata, with a finite (although very huge) possible number of states, each with state describing the position and location of every single particle in the universe. In this case, some people would say that the only ‘event’ which occurs to drive the automata is a simple time ‘tick’ – the state changes into a new state over discrete time periods, based upon the internal configuration of the world. What a lot of people don’t consider, however, is the possibilty that there are multiple events that could occur; time is just the one that we’re able to measure.
Going all the way back to the burrito example, what if we keep the system deterministic but just add a third possible type of event, which we’ll call C), but we won’t really describe other than that when event C) occurs, the burrito will go from being inside the fridge to being outside the fridge. The system is still deterministic, but it’s possible for the burrito to appear to exhibit ‘choice.’
What i’m trying to get at here is that perhaps choice exists, and the mechanism for choice is in the nature of the ‘events’ that occur, causing the state to transition. Most scientists see time as the only thing driving change in the universe – but if if there really was somethign called ‘good’ and ‘bad’ and these things existed as possible events that could happen. It’s easy to observe time because there are plenty of thins that all appear to change with ever ‘time’ tick of the world – but if if there are others that we don’t know about because our capability of the world is too subtle for us to understand?
If you’d like an example of a system that works exactly as I have described, consider video games. The primary mechanism by which tihngs change in a video game world is the time mechanism – object’s positiosn and velocities are updated as time changes. Things also change depending on which buttons the player chooses to press.
Our world could easily be an automata – this is something I have considered for a long time. What if there’s more than one symbol on the automata’s input tape? Curious, indeed.
[Crap, I just realized that nobody probably knows what I mean by 'input tape.' When automata theory was developed back in the 20's, the guys that worked on it imagined machines that looked at pieces of paper with little symbols written on them, the symbols corresponding in our case to the different types of events. ]
