A short story on biological life and consciousness

Context

Billion years ago, there were already rocks, water, gas, and many elements on Earth, as in many other places in the universe [1].

It seems that, around 3.5 to 4 billion years ago, somewhere in the oceans, in a place with specific rocks and gases, a specific chemical reaction happened [2]. This reaction, likely involving hydrothermal vents, resulted in the miraculous emergence of biological life. Life was enabled by the production of energy through chemical gradients across membranes (a difference in proton concentration that cells use to produce energy), which cells use to produce ATP, the energy currency of life [2].

This proto form of life evolved progressively, forming and following the rules of biological evolution:

• reproduction, or replication [3]

• genetic code, the blueprint for life, our DNA [4]

• inheritance, transfer of the genetic code from parents to offspring [6]

• variation, in the genetic code between individuals within a population [5]

• and selection, the fact that the genetic code of the individuals who survive is being selected over time [3].

Development

Over time, life evolved into diverse and more complex systems. They notably developed advanced sensors (vision, hearing, touch, smell…) and a capable brain. They can get a significant quantity of information and smartly process it, increasing their ability to analyze and act on their environment.

With specific brain architectures, some animals can take a significant step back on the information they get, perform complex computations on it, and enter "conscious" states. This is how I would define consciousness: the state created by the ability to take a step back on the information one perceives. For humans, this ability to take a step back is so strong that it allowed them to create complex concepts, develop language, use mathematics and many other things to represent what they perceive.

For a long time, only humans were considered conscious. But, if you observe a cat, a dog or a bird, you can clearly see that they take a step back on the information they receive, "thinking" before acting (or not acting). It is just not at the same level as humans do.

There are different levels of consciousness, different ways of being conscious, all rooted in the ability to perceive and take a step back. With this view, we can imagine that it is absolutely possible for artificial machines to be conscious, if they have those components. It will simply be different from the way humans and biological life do.

References

[1] Hazen, R. M. (2012). “The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet”. Viking.

[2] Lane, N. (2015). “The Vital Question: Energy, Evolution, and the Origins of Complex Life”. Norton & Company.

[3] Darwin, C. (1859). “On the Origin of Species”. John Murray.

[4] Watson, J. D., & Crick, F. H. C. (1953). "Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid". Nature, 171(4356), 737-738.

[5] Mendel, G. (1866). "Experiments on Plant Hybridization". Proceedings of the Natural History Society of Brünn, 4, 3-47.

[6] Dawkins, R. (1976). “The Selfish Gene”. Oxford University Press.