A Book Review: The Demon in the Machine, by Paul Davies
What is Life? A nine-star research update
This book poses anew the question: What is life? The narrative begins with two of my intellectual heroes: Edwin Schrodinger, and James Clerk Maxwell.
Before DNA was discovered both had put forth ideas about the role information might play in answering the question: What is life?
Recent experiments strongly suggest that they were not wrong. For this author reports that at the quantum (as well as at the cellular) level, information, energy, entropy and heat, engage in a quantum dance that results in cells becoming very efficient thermodynamic work-horses.
That is to say, at both levels, circumstances arise whereby, information, energy, entropy and heat all are interchangeable. Which essentially means that, "information," (an abstraction), can be rendered into a "physical quantity!"
(This is the first very big deal!!)
It seems that this is an interplay that cells have been taking advantage of since life came into existence.
In fact, as the author puts it on page 56: "Living cells ... contain a host of exquisitely efficient and well-honed nano-machines, made mostly from proteins. These bio-machines consist of motors, pumps, tubes, shears, rotors, levers, ropes, pulleys and other tools one could expect to find in an ordinary engineer's machine shop."
In short, living organisms are clever information manipulators, dodging the constraints of thermodynamics, reducing entropy as they change disorder into order.
(This is the second very big deal!)
The cell is a vast web of information processing and management. On its own, the information in a cell is static, but once a gene is expressed as a protein and combined with other data streams, it becomes a powerhouse of information processing.
However, here, by "information," we are no longer just talking about the Shannon bit-by-bit entropy formula, but also about genetic information that requires a global molecular context for its instructions to be recognized, executed and/or expressed.
We now know that to survive and be functional, a cell must be a good predictor of its environment, a smart manipulator and an effective storer of information. It also must be able to anticipate the future and make energy-saving moves as well as be able to avoid fatal encounters.
This requires an accurate internal representation of the outside world, a kind of virtual reality, or proto-consciousness.
It is this internal representation that allows biological organisms to act as their own agent in the world; and allows them to manipulate the external world, primarily harnessing its energy for their survival.
(This is the third very big deal!)
Thus, here, the author tells the story of life in two tightly woven narratives: one concerning the physical world of complex chemistry, the other about the abstract world of information.
His view is that to fully understand life, one must understand both its hardware (its molecular organization) and its software (its informational organization). Biological information is the software of life and its molecular organization is its hardware.
Fortuitously as it turns out, the software of biological organisms, parallels developments in mathematics and computer logic, especially their novelty and open ended-ness. Thus, logic and computer processing are the perfect tools and metaphors to study the inner workings of cellular life.
What was needed in life to cement the link between information and biology was the transformation of a purely abstract computational process into a physical construction process. Biological machines thus have evolved to fabricate components as well as to make copies of themselves.
DNA reflects the dual roles of first being passive data (as in a set of instructions), and then, depending on circumstances, also being a physical object.
The helix of DNA, for instance, is a physical structure that has embedded within it, informational instructions. The key to understanding DNA is that the very nature of its physical structure, the 3-D helix, conveys (abstract) information: Its form is also it function!
(This is the fourth very big deal!).
The decision to replicate an organism depends on a large number of factors throughout the cell and its environment; the decision to replicate is a distributed, rather than a top-down, one. That decision is not localized in one place. This distributed decision making is called top-down epigenetic control, or top-down causation.
In the simulated "Game of life," pixilated geometric objects are set in motion according to a set of logical and "state" rules. And, without any further intervention, these objects are let loose on a simulated world. Its ensuing information flows evolve into recognizable "cause and effect like" patterns just as organic structures in the real world do: both are independent of the physical substrate upon which they may exist.
(This is the fifth very big deal!).
In both cases, evidently higher-level informational rules of engagement create their own information patterns, and in turn, their own dynamic; and thus can be formulated at the level of abstract structures.
These structures create their own world of emergent activity with their own narratives.
So, as in life itself, "The Game of Life" too can be generalized to include more sophisticated rules including, with sufficient complexity, (rules that update a function based on changes in a given pixilated state as well as that of its environment), rules that would allow these artificially-created entities to evolve into self-referential and self-reproducing units that can even learn to copy their own instructions!
(This is the sixth very, very big deal!)
The experiments tracked by this author, show that many genetic traits are emergent, meaning, they evolve randomly and come into being only at the system level: that is, only when the system as a whole is taken into account. This includes entire networks of genes in interaction, as well as many epigenetic factors in the environment.
The important point here is that the flip-side of reductionism is systemic emergence - recognition that new rules, qualities and principles may emerge at higher levels of functioning and complexity without even knowing about the rules at lower levels of functioning.
(This is the seventh very, very big deal!).
The research strongly suggests that eventually we should be able to map molecular and biochemical processes onto a biological circuit board.
(This is the eighth, and ultimate big deal!!).
When we look at living things we don't see information, we see physical properties. Yet, the informational aspects hidden in plain sight, are as important as the physical things we see in the foreground. The information that makes up the unseen part, like the physical aspects of an organism, have also been sculpted by evolution for optimum fitness.
Whenever I see the question: what is life? I search for the answer to an even more puzzling but often unasked corollary: Where does the will for biological organisms to live, come from?
I read this book carefully, in the hope that by answering the first question, it might shed some light on the second one. And, at least indirectly, it did so.
The answer to my question is subsumed as a "given" here: Organisms possess the will to survive because, by definition, life got started struggling to become a self-sustaining process.
Everything that lives, does so only to survive, and only by sustaining its will to survive. That is its only raison de'tre.
(And that is the ninth and final big deal) Nine stars!