Friday, September 7, 2007

QV2: Is Free Will an Illusion?

The Quantum Veil
Part 2
Is Free Will an Illusion?

Our view of the universe has been radically transformed by the quantum revolution of the 1920’s. At first, this was not the case as quantum effects were minimized as only affecting the very small particles that we could easily ignore in everyday life. Outside of particle physics, even the sciences could usually ignore quantum effects as very small aberrations in an otherwise classical world. The disciplines of chemistry, biology and engineering could, for the most part, continue as though the objects of interest behaved as classical objects, unaffected by quantum indeterminism.

But key problems in understanding our universe persisted in the form of questions about the nature of life. If the universe is basically deterministic, with indeterminism relegated to the very small world of atomic particles, where does free will come from? Do we even have free will or is it an illusion? Is our whole system of law with its reliance on responsibility for our actions based on an illusion? Is the legal concept of premeditation based on the false assumption of free will?

It is interesting to note that the god in which Einstein proclaimed belief, “Spinoza’s God,” was a god for which freedom of choice did not have a place. For Spinoza, freedom of choice was an illusion, but Spinoza also held the difficult philosophical position that determinism does not diminish moral responsibility for our actions.

The question of free will is just the first and most obvious question raised if the underlying principles are deterministic. Besides justice, there is freedom, beauty, truth, faith, love, hope, understanding, insight, awareness, consciousness, happiness, loyalty, courage and the list goes on. Where do these experiences come from in a deterministic world? One explanation is the phenomenon of emergence. Emergence is the idea that certain complex behaviors and experiences arise de novo as systems become more complex. This type of explanation can be found in Darwin’s theory of evolution except that emergence is called adaptation and adaptation is shaped by natural selection.

I don’t think I can over emphasize the importance of this question. If the universe is deterministic, then there is no room for a God who “concerns himself with fates and actions of human beings.” One could still hold to the Deist’s God, but that god is easily deposed because such a god is irrelevant to daily life, a life filled with uncertainty, risk, heartbreak, happiness, anger, reconciliation, forgiveness and many other challenges of ordinary living. When Time Magazine proclaimed on its cover the question “Is God Dead?” in 1966, some 80 years after Friedrich Nietzsche first broached the subject, the question was really about the nature and relevance of God. It was the Deist God that had to die because that god was no longer relevant.

I am not saying that the converse is true. It is not the case that a non-deterministic universe proves the existence of God. But, if the universe is essentially non-deterministic, then the door is open for belief in a personal God who intervenes in history. One must come to this belief by faith; there is no other route. But if one has come to a belief in God by thoughtful meditation on life’s experiences or by sudden awakening, then the following arguments will show that belief in God does not contradict what is known about our universe.

Despite the alleged non-deterministic nature of the quantum world, there are two main ways the universe could remain deterministic. One way is that quantum indetermination could remain captive at the quantum level, with classical dynamics controlling all actions at the macro level, the level at which we live. The second way is that even if quantum effects do percolate up to the classical level, what if quantum indetermination is simply the result of our inability to lift the quantum veil? What if the quantum world is really deterministic as Einstein thought, but we simply cannot discover the rules because they are hidden from us? Both alternatives need something like a theory of emergence to explain the appearance of free will, justice, freedom, etc. I will call such a theory ‘deterministic emergence’ to distinguish it from other forms of emergence that allow for non-determinism.

The problem with emergence as an explanation is that it is not really a testable theory. We would like to be able to say what criteria must be met before something new emerges from complex systems. In fact, emergence is such a broad category of explanations, that it is not incompatible with quantum indeterminism. However, the logic path that will prove fruitful is the case where emergence is used to explain the presence of intangible experiences like free will when the underlying reality is deterministic. But in order for us to progress to the point of falsifying deterministic emergence in a deterministic universe, we must have a testable theory. We seem to be at an impasse.

Well, maybe not. There is a theory with sufficient rigor that we may well use it as a proxy for deterministic emergence. That theory is the theory of artificial intelligence, or AI. AI is the discipline within computer science that studies how machines learn. This is the area of robots and chess-playing computer programs. Within bounds, AI is a formidable theory. Already, chess and checker playing computer programs beat the best human players. Expert systems, a type of AI program, assist humans in certain skilled areas like oil exploration and medical diagnosis. AI programs can recognize human faces and human speech.

It is claimed by some proponents of AI that someday computers will be fully equivalent to a human being in every way including the ability to experience all of the normal intangible experiences of humanness. This is known as the ‘strong-AI’ viewpoint. Roger Penrose states it this way: “All thinking is computation; in particular, feelings of conscious awareness are evoked merely by carrying out of appropriate computations.” (Shadows of the Mind, Oxford University Press, 1994, p. 12.) Roger Penrose is a mathematical physicist who worked with Stephen Hawking when Hawking was developing his theories for ‘black holes,’ stars that are so massive that no light can escape. Penrose and Hawking share the 1988 Wolf Prize in Physics for their joint work. But Penrose is no champion of strong AI. He has written two books to argue that something non-deterministic must be taking place in human consciousness.

In order for the strong-AI viewpoint to replace deterministic emergence in our line of reasoning, we will have to replace ‘deterministic’ with ‘computational’ and ‘non-deterministic’ with ‘non-computational.’ Have we lost anything in translation? Not really, because, in theory, a computer can simulate any set of rules that can be defined. If fact, not all of the rules need to be defined if there is a rule or set of rules for generating and accepting new rules based on experience. There is no loss of generality by replacing a putative theory of deterministic emergence with computational AI. The only additional qualification we need is that ‘computer’ means a deterministic computer. Some day computers may be based on biological systems or even quantum actions. For now we will omit such possibilities because we are really interested in whether the universe is ultimately deterministic (or computational), and we have a suspicion that quantum systems and even biological systems somehow make use of non-computational activity.

In summary, here is our line of reasoning: If the universe is deterministic, there is no need for a god who cares about us and intervenes in our lives. Free will would be an illusion, a way of thinking we are making choices when, in fact, our choices are being calculated for us at some unconscious level. The universe may be deterministic because either quantum non-determinism is a result of our lack of knowledge as to what takes place behind the quantum veil or any real quantum non-determinism is confined to the small scale of particle physics. If we could show that human beings possess a capability that is impossible for deterministic computers, then we could show that something non-deterministic or non-computational must be taking place. In the next segment we will step through Penrose’s argument that people have access to truths that deterministic computers cannot reach. Following that we will tackle the more imposing issue: if the universe is non-deterministic then is it reasonable to attribute such non-determinism to God?

No comments: