The Matter of Existence - Why are we Conscious?

Philosophy encompasses a myriad of theories seeking to explain the seemingly unsolvable mysteries of existence. It is therefore only natural that it would seek to answer the dilemma of consciousness.

While some philosophers have argued that the world is only made up of physical things, an idea known as reductive physicalism, it is more common to suggest that there are both physical and mental constructs (substance dualism) (1). The implication of this is that the mind and body, entities with juxtaposed natures, can be considered to interact. This theory of interactionism gives rise to the mind-body problem: how can two ostensibly separate entities have effects on each other?

The quintessential definition of the exploration of consciousness in philosophy is arguably qualia – instances of first-person experiences, always subjective, since they can only be experienced by one person (you), in a certain way. Nobody else can undergo the same changes in being as a response to specific stimuli in a given moment, as you do. But what is it that gives rise to qualia, or even makes them possible? Why is life experienced in the first person?

In the attempt to answer such questions, not only philosophers, but also neuroscientists, have imagined increasingly strange scenarios, such as the philosophical zombie, in order to test certain assumptions about consciousness.

Furthermore, the prevailing theories of philosophy on consciousness leave out many questions to be answered: if physical and mental entities, especially the body and mind, interact, then how do physical objects influence mental constructs – how is the brain linked to the mind? And why was epiphenomenalism (the idea that only physical states can give rise to mental states, and not the other way round) first considered and accepted?

To weigh up the answer to these questions, we should perhaps proceed the explanation to more recent, scientific theories.

NEUROSCIENCE

Both philosophy and neuroscience agree that the source of consciousness seems to be the brain. Neuroscience, however, seeks to obtain the exact roots of conscious experience, and so suggests that there must be certain neuronal mechanisms that are 'jointly sufficient for any one specific conscious percept', resulting in specific patterns of neuronal activity being associated with each and every conscious experience (2). This idea is termed neuronal correlates of consciousness or NCC, and it has been studied through the use of fMRI brain scans to find the correlation between brain activity and certain stimuli, in the hope of finding the neural mechanisms that are associated with consciousness itself.

However, the NCC approach does not tell us which specific brain structures are enough to generate and sustain consciousness, because consciousness is a complex thing: even if neuroscientists found the NCC of an individual adult human, this does not mean that the finding is reflective of the 'essential nature of consciousness in all its forms'. As the author of the book Being you, acclaimed neuroscientist Anil Seth states, 'there are as many ways of being conscious as there are different conscious organisms', so the concept is not just difficult to measure, but to define.

It is assumed that one can discover whether a system (a being or an object) is conscious if one can imagine what it is like to be that system (3). Can you imagine what it is to exist as a human? If yes, it indicates that humans are conscious. A bat? You can probably imagine what it's like to be a bat. What about a thermometer? Can you imagine what it is to exist as a thermometer? The argument that a thermometer is not a conscious system resides in the fact that an object like a thermometer only works due to the laws of physics, and so does not need to have an underlying consciousness. But does it? And more importantly, does this imply that the systems that are conscious are so because they need to be?

Considering what neuroscience, and recently, physics (more on that later) have shown us about the brain, what appears to be a conscious system is in fact made up of minuscule, non-sentient objects, from the components of neurones to atoms and quarks, whose sole 'purpose' is to obey the laws of physics. Following the line of logic we started above, a new problem arises: what differentiates the non-sentient system from the system made up of non-sentient components? Why should fundamentally unconscious components give rise to a conscious, subjective, consistently first-person experience? As you can imagine, this has suitably been termed the 'hard problem' of consciousness.

Neither science nor philosophy seems able to answer this question, although neuroscience has made impressive attempts to quantify the missing piece of the puzzle.

More recently, a different kind of theory was proposed. In his book, Seth outlines how neuroscientists Tononi and Edelman came up with the suggestion that all conscious experiences are both informative and integrated (2). The adjectives have different but specific meanings: 'informative' refers to the idea that every conscious experience is different – each brings in new information, new combinations, they are all unique; 'integrated' is a more abstract notion, which implies that every conscious experience appears as a unified scene – you experience all the five senses at once, for example. Tononi and Edelman's conclusion is that given the nature of conscious experience, the neural mechanisms that underlie it must also be both informative and integrated. Another surprisingly suitable name: Integrated Information Theory, or IIT. An implication of IIT is that the system – the whole – must be more than the sum of its parts, in the informational sense. This allows neural mechanisms, generated by inherently non-sentient components, to enable consciousness. There is even a measure for this, called phi (pronounced fi), which quantifies by how much as system is more than the sum of its components. In other words, phi attempts to measure that something which enables non-conscious 'stuff' to entertain conscious experiences. As phi increases, so does consciousness; but does this mean that phi is consciousness? And so, what is phi made up of, exactly?

If phi measures the difference between a conscious and unconscious system, at what point does a system become conscious? (3) Imagine building a human from the very basic building blocks, starting from quarks, atoms, then cells, tissues, organs and so on. At what point do you consider that the human being built is conscious? Was it the addition of a brain? Or the addition of enough components to reach some kind of threshold? Some theorise that consciousness is a binary state, while others, for example Seth, prefer to consider levels of consciousness as moving through 'sharpish transitions', accepting that this kind of experience may be 'manifesting itself in different degrees, maybe even along different dimensions', which makes the separation of how conscious a system is and what the system is conscious of, meaningless (2).

Going even further, why should consciousness exist at all? I invite you to take a stroll through a now classical though experiment of epiphenomenalism: the philosophical zombie (3). Imagine a system that looked just like you, behaved like you, but lacking consciousness. It's likely that you were able to imagine this. So now, a fascinating question arises: why didn't nature just produce non-sentient zombies instead of conscious beings like us humans? Furthermore, why should this subjective, first-person experience accompany the largely unconscious processes that enable bodily function?

These questions would take, and have taken, hundreds of years to debate. It is truly puzzling to consider the matter of existence, but the reality of consciousness is what even makes these questions possible. However, in order to perhaps come closer to measuring and quantifying some aspects of consciousness, neuroscience focuses on what Seth calls the 'real problem': explaining, predicting and controlling the phenomenological properties of conscious experience (2). Eventually, attempts such as IIT and phi may allow us to teach our children and grandchildren why the colour red is red, and not anything else.

PHYSICS

As we said earlier, the brain is only made up of biological structures such as neurones and glial cells, blood vessels and tissues, but also of the materials at the foundation of all matter – atoms, and everything else within them. In other words, the components of the brain do not only obey classical mechanics at the macroscopic level, but quantum physics too, at the subatomic level (4). Therefore, quantum events undoubtedly occur in the brain as everywhere else in the physical world.

This is the basis for objective reduction, the theory which postulates that quantum processes enable consciousness, and that they take place inside neurones, at the level of a structure known as microtubules.

Microtubules are polymers of tubulin, forming part of the cytoskeleton, which maintains the shape of the cell and plays a crucial role in the process of cell division. These structure have been observed to respond instantly to mental events in thousands of places throughout the neurone, simultaneously (5). The theory proposed by Roger Penrose, who won the Nobel Prize in physics in 2020, and Stuart Hameroff, Professor of Anaesthesiology and Psychology, and Director of the Centre for Consciousness Studies at the University of Arizona, suggests that microtubules form a natural fractal pattern, allowing complexity to emerge from simple repeated patterns, due to the fractals' infinite intricacy (6).

The Penrose-Hameroff theory was dismissed outright, mainly due to the fact that the laws of quantum mechanics can usually only be applied at very low temperatures; for example, quantum computers currently operate at -272*C. The human body works at room temperature, so it is expected that it's governed by classical mechanics. Moreover, no one has ever been able to measure the behaviour of quantum fractals inside microtubules in the brain. However, some scientists are getting close, as they measured quantum fractals in the lab. You can read more about their experiments here: Can consciousness be explained by quantum physics? My research takes us a step closer to finding out (theconversation.com)

Could our experience be governed by quantum consciousness? Would this solve the mind-body problem, or explain qualia? The rapid advances in quantum physics and its vast applications may soon allow us to find out.

ALTERNATIVE THEORIES

Returning to the earlier idea that consciousness arises when a system is more than the sum of its components, could it be that the parts of the system have in fact some level of consciousness, too low to be measured directly and independently, but sufficient to add up to measurable amounts when constructed in a specific, 'correct' way? (3) This is the idea at the centre of panpsychism, which argues that consciousness permeates all matter. Although more of a philosophical idea, since neuroscientific measurements such as NCC or phi have failed to quantify the consciousness levels of a rock, for example, panpsychism could explain why phi exists as a notion, and could even lead to future theories bridging philosophy and neuroscience.

But what if matter, on Earth, in space, and everywhere else was not a physical entity, but a mental construct? What is consciousness, rather than matter, is the foundation of the universe? (7)

This radical shift in the hierarchical status of consciousness belongs to a heavily debated theory, called biocentrism. By this line of thought, the existence of consciousness can be explained by biocentrism, where most if not all other prevailing theories of philosophy have failed. The philosophical zombie scenario breaks down: consciousness exists because everything else does, and everything exists because of consciousness.

Despite not being supported by empirical evidence, as our current understanding of the world strongly suggests that the universe is physical since we can measure it, perhaps we should take a different perspective. Biocentrism cannot be tested objectively because it presents our representation of reality as inherently subjective. Within science too, it seems that the only way to measure an intrinsically subjective concept is a subjective method, which is why scientific studies of consciousness often involved introspection. Thought can be hammered into a nomothetic definition but cannot accurately be described as it is by anyone, except the individual experiencing the thought.

CONCLUSION

Throughout this varied exploration of ideas, a recurrent theme occurs: even with scientific and philosophical explanations, the question 'why does it feel like something to be something?' remains unanswered. And when I have unanswered questions, I like to turn to some ancient Eastern philosophy filtered through the distinctive, idiosyncratic lens of a modern philosopher.

Perhaps we do not only experience consciousness, but are consciousness, as Alan Watts, a well-known English writer and "philosophical entertainer" suggests (8). Perhaps, in the philosophical sense, we are meant to be conscious, simply through the fact that we exist at this point in space and time. Take it as a kind of evolution, biological coherence, non-scientific theory – whatever you wish; it's designed to be open to interpretation.

So, maybe consciousness is symptomatic of 'the scheme of things as the apples are symptomatic of the apple tree or the rose of the rose bush'. Maybe we, as conscious systems, are a symptom of the universe.

REFERENCES

1. CrashCourse. Where does your mind reside?: Crash Course Philosophy #22. YouTube. [Online] 2017. https://youtu.be/3SJROTXnmus.

2. Seth, Anil. Being you. 2021.

3. Harris, Making sense with Sam. Making sense of consciousness | Episode 2 of the Essential Sam Harris. Making sense with Sam Harris. [Spotify] 2022.

4. Stanford Encyclopedia of Philosophy. Quantum Approaches to Consciousness. plato.stanford.edu. [Online] 30 November 2004. https://plato.stanford.edu/entries/qt-consciousness/#ApplQuanConcMentSyst.

5. Jon Lieff, MD. Are microtubules the brain of the neurone? jonlieffmd.com. [Online] 29 November 2015. https://jonlieffmd.com/blog/are-microtubules-the-brain-of-the-neuron#:~:text=In%20neurons%2C%20microtubules%20respond%20instantly%20to%20mental%20events,are%20quantum%20computers%20and%20the%20seat%20of%20consciousness..

6. Smith, Cristiane de Morais. Can consciousness be explained by quantum physics? My research takes us a step closer to finding out. theconversation.com. [Online] 19 July 2021. https://theconversation.com/can-consciousness-be-explained-by-quantum-physics-my-research-takes-us-a-step-closer-to-finding-out-164582.

7. myhomebasedlife.com. Is Biocentrism Debunked? Science Behind Life and Consciousness. myhomebasedlife.com. [Online] 5 April 2023. https://myhomebasedlife.com/biocentrism-debunked/.

8. Feed Your Brain - Podcasts. Alan Watts - the nature of consciousness - lecture 1. Spotify. [Online] March 2020. https://open.spotify.com/episode/1c4H7RVxlLIcGaZMYs3eoD?si=39426097c4cc4590.