We all basically know what is meant by free will. Don’t we? We know for example that we get to decide what’s for lunch. We have the ability to choose between different possible courses of action. More formally, we conceive free will to be the capacity for an agent to make choices in which the outcome has not been determined by past events. On the other hand, many folk; those who take a philosophical position that for every event, including the things we humans do, there exist conditions that could cause no other event. That the notion of choice is merely an illusion. Nothing new - this problem has been in circulation in ancient Greek philosophy and remains a major focus of philosophical debate today.
But here’s a little twist. Is it just us living things that get to exercise free will? Can for example a microwave oven possess free will?
To go there, let me first talk about Alan Turing’s halting problem. Not withstanding the technical logic/mathematical framework – this work is historically important because it was one of the first problems to be proved undecidable. In computability theory for instance, the halting problem is the problem of determining, from a description of an arbitrary computer program and an input, whether the program will finish running or continue to run forever. Turing proved in 1936 that a general algorithm to solve the halting problem for all possible program-input pairs cannot exist.
A new Turing Test for free will can determine whether somebody, or something, thinks it has free will. And whilst your Microwave oven might fail this test, more complex systems – your phone for instance may well pass. Research suggests that that there are clear mechanisms in computation that make the outcome of a given calculation unpredictable, especially to the person or object making it. The key contribution of this latest work is a mathematical proof of this idea.
For many thinkers, the fundamental issue of free will is whether the deterministic laws of the universe can produce an intrinsically unpredictable outcome. If our thought processes are governed by these deterministic laws, then surely a given outcome is determined long before we begin to think about it.
The idea of Turing is used to prove that deciders; people or machines that make decisions cannot in general predict the results of their decision-making process in advance. In other words, the outcome of a decision is unpredictable by its very nature. The proof is an extension of Turing’s halting problem in computer science. This states that there is no general way of knowing how an algorithm will finish, other than to run it. What’s more, any attempt to determine the decider’s decision independently must take longer than the decider itself.
This means that when we have to make a decision, there is no way of knowing in advance how it will end up. The familiar experience of a decider does not know the final decision until we have thought it through. This is a necessary feature of the decision-making process. But, what of our ipods? As gadgets become more complex, they become unpredictable, even imperious, in ways that are all too human. It seems that complex gadgets possess all the criteria required for free will, and behave as if they it.