Defining life: reductionist physics does not work (Introduction)

by David Turell , Thursday, October 22, 2020, 18:37 (1493 days ago) @ David Turell

Life does not allow for reductionism conclusions:

http://nautil.us/issue/92/frontiers/why-physics-cant-tell-us-what-life-is?mc_cid=ab3f23...

"As we have gained an ever more accurate picture of how life’s tiniest and simplest building blocks fit together to form the whole, it has become increasingly tempting to imagine that biology’s toughest puzzles may only be solved once we figure out how to tackle them on physics’ terms.

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"Put another way, wouldn’t any proposed explanation for the emergence of life have to break it all down into a series of rationalized steps, where each next one follows sensibly and predictably from the last? If so, how is that not the same thing as saying we want to reduce life to a choreographed performance directed by a simple, calculable set of known physical rules?

"There’s no question that molecular biology has its own long and venerable history as a hard science in its own right. Thanks to countless experiments on molecules, cells, tissues, and whole organisms, it is now abundantly clear that the marvelously diverse functional capabilities of a living thing all have sound bases in the physical properties of their material parts.

"However, this is not to say that reductionism reigns; on the contrary, the “more is different” idea of emergent properties rears its head everywhere in the study of how life works.

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" Life is a grab bag of different pieces, some of whose physical properties are easier to predict mechanistically than others, and it is certainly the case that at least some of the factors that matter a great deal to how a living thing works will fall into the category of highly non-universal emergent properties that are impossible to derive from first principles.

"At base, this challenge will always keep popping up, because talking in physical terms is never the same thing as talking in biological ones, and so biologically important questions are not picked for their physical tractability. Instead, biological and physical ways of talking ground themselves in very different conceptual spaces.

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"In short, biology could not have been invented without the preexisting concept of life to inspire it, and all it needed to get going was for someone to realize that there were things to be discovered by reasoning scientifically about things that were alive. This means, though, that biology most certainly is not founded on mathematics in the way that physics is. Discovering that plants need sunlight to grow, or that fish will suffocate when taken out of water, requires no quantification of anything whatsoever. Of course, we could learn more by measuring how much sunlight the plant got, or timing how long it takes for the fish-out-of-water to expire. But the basic empirical law in biological terms only concerns itself with what conditions will enable or prevent thriving, and what it means to thrive comes from our qualitative and holistic judgment of what it looks like to succeed at being alive. If we are honest with ourselves, the ability to make this judgment was not taught to us by scientists, but comes from a more common kind of knowledge: We are alive ourselves, and constantly mete out life and death to bugs and flowers in our surroundings. Science may help us to discover new ways to make things live or die, but only once we tell the scientists how to use those words. We did not know any physics when we invented the word “life,” and it would be strange if physics only now began suddenly to start dictating to us what the word means.

Comment: The author's point is simple. Life is a emergent event=, which cannot be explained by reductionism and that applies to all thought about the origin of life.