Dienstag, 26. Juli 2016

What is consciousness and where does it happen?

 Consciousness is one of the many yet unsolved mysteries of our universe. Why is it, that there is this inner movie playing in our head, feeding us information about the environment we live in, making us feel about this information as we interpret it, bringing it into context with the memories of previous events we perceived in our conscious mind? While it should be of great interest to know about consciousness to all of us, we did not have a science of consciousness until very recently. Also there are the questions, “what am I” and “what is the world” that are both very closely related to the question of what consciousness really is. How can we try to understand the universe if we don't understand understanding?

While there was no science of consciousness, there has been a philosophy of consciousness since the beginning of philosophy itself. The philosophy of consciousness tries to understand what consciousness means. It does so by trying to find a language with which we can describe this inner movie we experience. Philosophers ultimately came up with two classes of problems we need to solve if we try to understand consciousness. They defined those as the “easy problems” and “the hard problem” of consciousness. In short, the “easy problems” are all those problems that a deterministic machine could solve. Easy problems are functions of our brain like categorizing sensual input and evaluating it, or focusing the conscious self on a specific task or problem.

The hard problems are those functions of consciousness that are specific to our inner self. Why do we “feel” the color black as much as we see it and what do we “feel” when we recognize it. The hard problem concerns numerous qualitative associations we make when we communicate or perceive. Why is there a feeling of the color red in the evening sky that we just cant explain? Why is there a harmony we feel when listening to music that changes our consciousness? All those aspects of the human mind concerned with “how does something feel” are called qualia.

David chalmers is a prominent member of the circle of philosophers of consciousness and I recommend watching his TED lecture here:

For me the most important and hard questions are, what is free will? How does it happen? What is creativity? How do we invent? How do we understand?

For me those are the most obvious differences of a thinking mind and a machine.
Naturally those questions don't concern you, if you think that a machine could do those things. As described in the previous article, the idea that consciousness is actually an illusion has many prominent followers. Are there alternatives? 

Obviously consciousness can be tampered with or taken away on any number of ways, like too much alcohol or drugs or a hard hit on the head. It must therefore be some function in our brain that is based on chemical reactions, but where could that be?

Other than the "deterministic" theory of consciousness, that says that free will is just an illusion, two theories of consciousness are competing today. 

In the field neuroscience one theory of consciousness has established itself a few years ago. In the so called “phi theory of consciousness”, consciousness emerges whenever integrated information systems reach a certain complexity (phi). Giulio Tononi formulated this theory and its also called the Integrated Information Theory of consciousness. In his view consciousness could emerge anywhere a certain threshold of information and integration is reached. 

There is much good to be said about this theory. Emergent phenomena are quite commonplace in our universe. Wavelike behavior i.e. seems to emerge everywhere we look. Waves behave fundamentally similar regardless of where they emerge. Waves in water or air, or electromagnetic waves like radio- or light waves, they all share a common principle of behavior.

But as theories go, I still feel the IIT is not explaining very much. While it acknowledges the existence of the hard problem of consciousness by adding the “miracle” factor of emergence, in my opinion it falls short in explaining free will or understanding. For neuroscientists the brains function is a product of the neurons alone, and neurons behave just as deterministic as a computer. There is nothing in Tononis theory that prohibits Ray Kurzweil from downloading his mind into a computer soon.

In the IIT, there is no place where randomness and interaction with the rest of the universe comes in. How evolution could start the process of gradually developing consciousness with the Paramecium and reach the human mind is hard for me to see when looking at the problem with the IIT perspective. Only if consciousness is something that Paramecium already has, the evolution of human (or raven or dolphin) consciousness could be explained. A Parameccium has no neurons, as it is a single cell organism, how can the paramcium therefore have consciousness? On the other hand, if the Paramecium has consciousness, why not any of the systems that call themselves artificial intelligence today? Surely they are pretty integrated. What are the sophisticated AIs missing that unicellular living organisms, like a Paramecium, might have?

As mentioned in the previous article, I believe that factor to be a quantum behavior of the brain. The distinguished Oxford physicist Roger Penrose, the teacher of Stephen Hawking, is the author of another theory of consciousness that is discussed today. He published the idea that quantum behavior might be at the core of understanding consciousness in his provocative book “The emperors new mind”.

He also argued, that randomness alone would not be enough to explain the hard problems of consciousness, such as free will. He therefore proposed a very sophisticated theory of quantum mechanics that incorporates parts of relativity theory.

In the previous article I wrote, that nothing in quantum mechanics stops us from putting the results of the double slit experiment in a “safe” and wait for a hundred years until we decide to observe the wave pattern or the particle behavior of the experiment.

This is a version of the “Schrödinger Cat” thought experiment. It was formulated to express the incompleteness of quantum theory for wave functions of “large scale”. Basically, quantum behavior only ever is found in small scales. There is simply no wave function of cats that we can find, just as there is no wave function of planets or suns. As Penrose says:

In my own view, the non-existence of linearly superposed cricket balls actually is contrary evidence!... We know that at the sub-microscopic level of things the quantum laws do hold sway; but at the level of cricket balls, it is classical physics. Somewhere in between, I would maintain, we need to understand the new law, in order to see how the quantum world merges with the classical. I believe, also, that we shall need this new law if we are
ever to understand minds! For all this we must, I believe, look for new clues.”.

Therefore he proposes there is a principle we do not yet understand behind the collapse of these wave functions or “reduction”. Roger Penrose then went ahead and formulated a principle that collapses the wave function as a factor of the energy/mass displacement that a quantum state would produce. Whenever this displacement grows the chance of a spontaneous reduction of the wave function increases.

In the emperors new mind, he formulates the idea, that somewhere in a brain there is a part where this collapse of the wave functions happens not at random and not deterministic, but “orchestrated”. Somewhere in our brain the gap between the classical and the quantum world is closed.

His theory therefore basically says that, consciousness is a fundamental principle of the universe that we make use of, just like space and time. Not “the observer”, but “consciousness” is what collapses the wave function. Consciousness as a fundamental principle is not to be understood in a way that ascribes the universe with a thinking mind, but the other way round. We, as all life, make use of this fundamental principle to gain free will and understanding. 

I recommend this video of one of Roger Penroses lectures. He proposes a strictly mathematical argument for the non deterministic nature of the brain that is truly fascinating if you are inclined to find math fascinating. 

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