Consciousness. We all say it, we all understand what it means, but good luck to the sorry soul who tries defining it. The word has developed an almost mystical connotation. But is it just our arrogance and bias towards human exceptionalism that gives this idea so much value? Ultimately, is consciousness just a consistency within the brain, a monitor through which “we” experience life? Or is it something that varies in quality and can be understood in greater detail through the lenses of science and philosophy?
The mind-body problem
At the Schrödinger at 75 conference, Professor Michael Gazzaniga of the University of California decided to take a concept from within physics to discuss how philosophy and physiology clash. That idea was complementarity, the concept of two contrasting theories, such as the wave and particle theories which are central to quantum dynamics. The clash between philosophy and physiology is referred to as the mind-body problem; the question of how thought relates to the brain.
In the case of consciousness, two contrasting perspectives emerge. On one side, there is the molecular basis for consciousness: such as the firing of neurons and the release of neurotransmitters. On the other side is our experience: our relationship with others, our appreciation for art, and our understanding of the world around us. On the latter side, thinkers have been using philosophical rationalism to glean an understanding of how we perceive. On the former, cognitive scientists have been using the scientific method, birthed from the work of philosophers, to develop an understanding of our subjective experiences through objective mechanisms in the brain.
Our experience and what science tells us about the brain seem like two parallel narratives that may remain incredibly close, but infinitely unlikely to cross. The theory put forward to explain this epistemic gap is that of emergence, which is the idea that the whole is greater than the sum of its parts. A classic example of emergence is seen in the grains of sand in a pile, none of those individual grains have the trait of “pile-ness”, yet they form a pile as a collective. This idea is even more applicable to the formation of our societies. Unlike grains to a pile, societies are not made by staking individuals on top of one another, but by interactions, which allow for an additional layer of complexity between us and our societies. The same can be said of neurons in the brain, as each can be connected with up to 10,000 other neurons, increasing the organisation of the system, and the complexity of its emergent properties immensely. As American biologist Howard Pattee said: “Life is seen as a layered system and each layer has its own vocabulary.” According to Gazzaniga, the gap between the body and mind exists between two of these layers. Each layer is as real as the other. The higher order layer of the mind could not exist without the body at its foundation. However, currently, any individual’s mind cannot be encapsulated by generalised models of the brain. Gazzaniga calls for complementarity as a means of understanding these individual, conflicting layers of interpretation.
Theories of consciousness
There are currently three very popular theories of consciousness, two of which – Global Workspace Theory (GWT), and the Integrated Information Theory (IIT) – were talked about by Professor Christof Koch at Schrödinger at 75. GWT is the idea that consciousness is a byproduct of the movement of our working memory across time. Different stimuli are vying for our attention, and the strongest of these stimuli are the ones that we become aware of. This is a functionalist model, which means that anything, given appropriate complexity, could compute its way to consciousness.
IITis a mathematical model favoured by Koch himself. IIT rests on the assumption that if a conscious experience can be fully accounted for by the underlying physical system, then the properties of the physical system must be constrained by the properties of the experience. To phrase it in terms of emergence, the higher order emergent layers have a strong feedback to the layers below them. This theory argues that, although a computer may be able to model consciousness, it would not be able to have consciousness. Just as a computer can model gravity, it does not have the “causal power” of gravity. It does not suck a researcher into a singularity when she runs a computational model of a black hole.
“Just as a computer can model gravity, it does not have the “causal power” of gravity. It does not suck a researcher into a singularity when she runs a computational model of a black hole.”
The main difference between these two models is the moral status of an artificial general intelligence. GWT posits a more panpsychist model, meaning consciousness is a universal entity that can be picked up or developed by anything of sufficient complexity. IIT implies that even if a computer passes the Turing test, it could never be conscious. One may argue that this is a dangerous theory, and proposes a border for our empathy. After all, if a person acts conscious, we treat them like they are conscious, even though we can never confirm it. Why should it be different for a computer?
“After all, if a person acts conscious, we treat them like they are conscious, even though we can never confirm it. Why should it be different for a computer?”
Consciousness as an illusion
The last theory of consciousness is that of Professor Daniel Dennett, the keynote speaker at the conference. Prof. Dennett developed the Multiple Drafts Model (MDM) almost thirty years ago in his book ‘Consciousness Explained’. Though this theory draws on ideas from the other two theories, it differs from them in some exceptional ways.
Prof. Dennett avoids coming to the seductive conclusion that we feel conscious, therefore we are. He contrasts the views of American philosopher John Searle when he argues that there is no single place in the brain where things all come together to give rise to consciousness. This is in direct conflict with the popular philosophical theory that a Neural Correlate of Consciousness (NCC) exists, the bit in our brain that is on when we are conscious of something. This point, where mind meets matter in its conception, was thought by René Descartes to be the pineal gland. Although Descartes had many fantastic ideas that led to the growth of new fields of intellectual exploration, it is safe to say that one’s soul being attached to one’s pineal gland wasn’t one of them. By outsourcing the problem to an internal interpreter beyond our examination, this theory undermines the necessity to understand perception.
On the other hand, Dennett suggests that at the Cartesian theatre, stimuli reach their associated position on the cerebral cortex, and they enter our conscious awareness. Some of his critics have accused Dennett’s model of existing outside of possible verification, though it still remains the leading theory. In its defence, it may be that consciousness itself lies beyond verification.
“So long as we set new understanding and new perspectives, rather than the ever-shifting horizons, as the goal, then we’ll find enough to keep us busy for however long consciousness hangs around in this universe.”
There is a worry that our understanding of consciousness will only ever asymptotically approach its actual intricacies, and that its direct pursuit is like the direct pursuit of happiness – exciting in theory, but fruitless in reality. Is it true to say that the more we understand about our consciousness, the more it adds to its complexity? This may be true for much of science and the pursuit of knowledge, as every new discovery shifts our perspective, so that we now see areas of enquiry which were once blind to us, and ask questions we once could not fathom. So long as we set new understanding and new perspectives as the goal, rather than the ever-shifting horizons, then we’ll find enough to keep us busy for however long consciousness hangs around in this universe.