This is part of a series: Define Life
I found an interesting view on what life is: Life is a Process, Not a Thing – The Mantle. In it, JoJo Brisendine argues that life is best understood not as a system that copies and spreads a particular strand of DNA, but as a system that neutralizes free energy.
It’s a reductionist view that emphasizes the flow of energy in living things above all, and says that every other part and phenomenon related to life is a natural result of that process. It’s a reaction against 2 other views:
- Ferris Jabr – Life is nothing more than a concept – life does not really exist
- The currently popular view among evolutionary biologists that RNA is the original self-copying molecule that eventually turned into us
He says that the explanation for the complexity of life – an ever-thorny problem for evolutionists – is that living things are the path of least resistance for energy to flow. DNA didn’t come first, RNA didn’t come first, proteins didn’t come first – metabolism came first. He uses lightning as an example. Lightning follows the path of least resistance, and thus can flow through air at significantly lower electrical resistance than one would expect if assuming that air is completely uniform.
He speculates that perhaps, billions of years ago, some kind of chemical “path of least resistance” appeared that became self-sustaining. The results of the reaction made a positive feedback loop, and any “mutant” chemicals that made the reaction happen faster tended to become the new normal over time. He thinks that this hypothetical “chemical evolution” eventually created every living thing on the planet.
Before I explain why, let me give you a little background. A big weakness of naturalism – the belief that there is nothing supernatural, and “the universe is all there is” – is that our current knowledge of chemistry says that life can’t appear by any known natural processes. If someone found a way, odds are that every college chemistry student would create life in a test tube. Furthermore, many chemicals and structures in living things decay quickly after death, and some entire classes of chemicals – such as lipids – are not known to appear in nature except when a living thing creates it. Thus, the best that naturalists can currently do is speculate wildly on how life or some kind of “pre-life” appeared.
Two other ways that naturalists have speculated that life appeared are:
- Amino acids first
In this view, something – typically lightning – created some of the building blocks of proteins. Eventually, a self-catalyzing “protein” appeared, and its descendents eventually became all of us.
- RNA first (RNA world)
In this view, RNA came first. RNA is a DNA-like molecule that performs some functions of DNA and some proteins. The article I linked to rebuts it pretty soundly.
His metabolism-first hypothesis is similar to Biochemical Predestination and suffers from the same flaw: self-organizing systems don’t become ever more complex. They instead follow certain patterns that come naturally from the laws of physics and the force/phenomenon that creates them. In the case of biochemical predestination, Kenyon and Steinman argued that self-organizing systems would evolve pretty much without limit. In the case of metabolism-first, Brisendine argues that positive feedback loops can and did become ever more complex essentially without limit.
If he was right, we should expect that living things would tend to dissipate free chemical energy far faster than it would without them. But this is absurd. Life has the opposite effect. Not only do living things tend to store energy that would’ve otherwise dissipated – including chemical energy – but they tend to create an even bigger imbalance of chemical energy. Plants, and all other photosynthetic creatures, release oxygen into the atmosphere. As far as I know, earth is the only planet with a significant amount of oxygen in its atmosphere. This is because free oxygen is very reactive and it tends to eliminate itself by reacting with things such as iron.
Although I think that his metabolism-first hypothesis is bunk, I’m intrigued by his claim that life is best understood as a process, rather than a thing. If this claim of his is correct, it would explain why it seems like life is always doing something. It would also explain why we use the term “living” to describe something that’s alive.
Strengths of thinking of life as primarily a process:
- It seems like every living thing is doing something
- It explains why we use the term “living“
Weakness of thinking of life as primarily a process:
- As far as I know, living things are exceedingly complex machines that cannot be generated by mere energy flow. Thus, any correct definition of life must acknowledge that an integral part of life is its machinery. It isn’t just the result of something else.
This weakness of “life as a process” means that it’s not a complete definition. But I do think that a very fundamental property of life is that it sustains itself.