I am a great admirer of Douglas Hofstadter, author of “Godel, Escher, Bach” and indeed that book, along with “The Mind’s I” are among two of my favorites. These are both books which have been some of the most influential and most inspiring in my overall understanding of nature itself, and yet I was never able to agree with Hofstadter’s premise on the nature of consciousness.

You see, Hofstadter is a functionalist; in simple terms, that means that he believes that the nature of consciousness is strictly the act of carrying out an algorithm regardless of the physical makeup of the action. That’s a fairly technical description and so the following illustration should help to better clarify what it is a functionalist believes.

As you likely know, your brain is made up of trillions of atoms; furthermore, the atoms that make up your brain today are not the exact same atoms that made up your brain even 2 minutes ago, a very small number of them will be replaced or swapped out by other identical atoms. Most people, however, would agree that they are the same “consciousness” now as they were 2 minutes ago, despite the fact that their physical composition has changed. Indeed, over the course of no more than 7 years, ones entire brain will consist of entirely different atoms, despite the fact that one would nevertheless argue that they are the same consciousness. Thus consciousness, it is argued, has nothing to do with physical composition.

The atoms of a human brain and of the nervous system in general are organized into cells called neurons, and these are the most fundamental cells responsible for transmitting information around your body. Neurons transmit information such as pain, vision, hearing and all other senses to your brain; furthermore neurons transmit information from one part of your brain to another.

Now assume that a Bob was selected for a long term experiment where the first phase of this experiment was to just replace a single neuron in his brain with a very tiny mechanical unit, like a silicon chip. The unit would act in a manner indistinguishable from that of the original the neuron, but the unit was instead created inside of a laboratory by a team of scientists rather than from naturally occurring biological means. The functionalist would argue that in the same way atoms in the brain get replaced by new indistinguishable atoms all the time without any change of consciousness occurring, no change of consciousness would occur at all by replacing a biological neuron with a mechanical neuron. That is, so long as the mechanical neuron can carry out its action in the same manner that the biological neuron can, no change in consciousness occurs.

Alright, so let’s say that after 7 years, all of Bob’s biological neurons had somehow been replaced by mechanical neurons. The argument is that even though Bob is now composed entirely of silicon chips, he will nevertheless be conscious, and that in fact his consciousness is the same Bob today as it was 7 years ago.

The absurdity of functionalism occurs when lifting the restriction, as we have imposed on ourselves, of limiting consciousness to the confines of a human brain. As is pointed out in the famous thought experiment by Ned Block, neurons are incredibly simple cells to understand, there is nothing magical or mysterious about an individual neuron. The description of how any individual neuron behaves and interacts can be described entirely in less than a single page. Since it is believed that the human brain has about 1 billion neurons, and the population of China is roughly equal to 1 billion, let’s assume that instead of replacing all of Bob’s neurons with silicon replicas, we just create a copy of Bob’s neurons one by one, by writing out the description of each individual neuron on a sheet of paper, and giving that sheet of paper to a single Chinese inhabitant. After 7 years, every citizen of China will have a piece of paper describing some very simple rules and instructions that correspond exactly to a single neuron in Bob’s brain.

Is China now conscious? Is China now Bob? What is the difference between replacing all of Bob’s neurons with silicon chips, and replacing all of Bob’s neurons (or in our case duplicating them) with the citizens of China?

Visualizing this reminds me of the Matrix Revolution’s when Neo confronts Deus Ex Machina. The consciousness behind Deus Ex Machina is the all powerful Architect, and to manifest himself physically outside of the Matrix he simply brings together an entire swarm of Sentinel’s to form a face, where each Sentinel acts as a tiny cell of Machina’s being. The concept works elegantly for the movie, but in reality there seems to be something rather dogmatic about the assertion that since all of China is carrying out the actions performed by Bob’s brain, that somehow China is a conscious being.

I do not mean to trivialize functionalism, on the contrary it is certainly difficult to argue that if one replaces biological neurons with something artificial, that the artificial being will not act and behave as the original. The argument against functionalism is that this artificial being would lack the comprehension of its actions, in much the same manner that a chess playing program lacks any sort of understanding of what it’s doing even though it might end up defeating a human Grandmaster chess player. Functionalism can not account for what I believe is the most crucial aspect of consciousness; that is the self-awareness component. Deep Blue, the IBM computer mainframe that defeated International Grandmaster Gary Kasparov at chess, while perhaps very similar in behavior and in action to Gary Kasparov at chess, lacks the self-awareness of its own actions.

Self-awareness is, in fact, what put an end to the ideal that the foundation of mathematics could be put on a solid footing. As Kurt Godel showed, whenever a system even so much as hints at the possibility of a self-referential theorem, that system is subject to either inconsistencies, a property most dreaded by mathematicians, or incompleteness, a property which denies any sense of complete satisfaction to mathematicians. And yet we, as conscious beings, allow for and even ourselves make self-referential statements constantly without breaking down. The fact that we can accommodate this should suggest that our consciousness is performing something that can not be replicated functionally. It is thus the breakdown that occurs when self-reference is introduced into a mathematical or computational system that I feel makes both of these fields unsuited to understanding consciousness. We may, and in fact I firmly believe will, manage to construct artificial beings that can very accurately mimic the actions of actual biological entities, yet I maintain that actually getting these entities to become conscious and actually aware of their own existence to be a feat wholly impossible using mathematical or computational methods.