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Comment by intrasight | Hacker News Reader

How did living things get so reliable without proof?

Living things aren't very reliable. They don't last very long, in general, and their replication mechanism is highly error-prone.

I get that we have mouths, vocal chords, lungs, brains, etc. It simply shocks me that some fellow humans use them to ridicule those things.. Once machines start making fun of us as they heal themselves (something we can do too.. go Life), I believe I'll get their humor, or what have you. I wonder if with their "big brains" some of them will still feel so inclined to speak unkindly about Earth's chemicals and processes that their bodies use.

Neither is software, for that matter.

That's an extremely narrow view of life. A broader view might be that life on Earth began a few billion years ago, and has managed to hang on ever since. Do you realize that you are, most likely, the direct descendant of one of those early lifeforms? Every single one of your ancestors, for billions of years, has managed to produce viable offspring in an unimaginably long chain of living organisms. How can you call that unreliable? Sure, bits of your DNA are being corrupted every second. Sure, tens of billions of your human cells die and are cast away each day. And, sure, each agglomeration of cells we call a human only lasts a few tens of years. But life has enough redundancies, contingency plans, and diversity that it will in all likelihood keep going for a long, long time.

Having a single instance of a particular organism last for a long time just isn't what life is about. If you look at the full context of what life is doing, it is way goddamn more reliable than anything humans have designed, proofs or not.

I agree with your argument as far as it goes, but if you're responding to me, you're making a straw man argument. I was saying that living things (i.e. individual organisms) aren't very reliable; you're saying that life is very resilient. That's a true statement, but utterly non-responsive to the point I was making.

Individual organisms are incredibly reliable when you consider the range of functions they perform. Compare, say, a quadcopter drone (or any other small air vehicle) with a parrot.

Lifespan without service or repair? Drone, weeks. Parrot, decades.

Autonomy before recharging/refueling? Drone, 20 minutes. Parrot, hours to days.

Cognitive faculties? Drone, slim to none. Parrot, long term autonomous in complex environments.

Reproduction? We can't build things that do that at all yet, let alone pack one into a 1kg autonomous aircraft.

Yes, we can build simple machines to replicate one function of a living creature, and those machines will be more reliable over short durations, but only because they are orders of magnitude simpler. You might as well call an LCD screen "unreliable" because it won't outlast a photograph.

From modern evolutionary biology's perspective "individual organisms" are NOT the "basic units/modules etc." of life. The basic ones are genes at the core informational level level and species at more loose and macro level.

So the living things to software analogy would be more like:

- gene == source code of a program's module (like an "independently testable unit of code" - natural-selection + sex-based recombination are actually the tests)

- ... (organizational levels with with no direct analogy to software go in between)

- individual organism == set of processes (running instances of programs) running together with heavy inter-process communication

Then at a higher level, genes and their manifestations constitute the "hardware" (more like a VM), run the software called "memes", with its own organizational patterns that are outside the field of biology.

What you call living thing or individual organism is, from "life's perspective", closer to a transient group of running processes that can be killed at any time because their sources and binaries are safely stored as genes or memes. Your body and your psychological self are closer to "running threads of nginx on a particular server handling a particular set of requests" than to "the program nginx itself" in source or binary form :)

In a discussion, it is not unreasonable to say that if you widen your view a bit, you will find a greater truth.

What do you mean by "most likely"?

Each living individual is an uninterrupted continuum of living cells (sometimes reduced to a single living gamete) back to the origin of life, whatever it was.

Compared to what? Some trees are very old. There's a bristlecone pine tree in California that has been around since before man knew how to smelt iron. What reproduces better than living things? Virtually nothing made by human beings is expected to last that long, let alone something as complex and intricate as a tree is. Some buildings, by luck and continuous maintenance, may last as long - but they don't self reproduce and only stay standing through massive ongoing repair.

True enough, but for every bristlecone pine or ancient yew tree, there are billions of bacteria that live mere days and insects that live a few weeks or months. In addition to vastly outnumbering them, I would wager that all the insects and bacteria of the world probably outweigh all the 500+ year old trees currently in existence.

To really stretch the analogy, there are also millions (perhaps billions) of short-lived, abandoned software projects that never grew into something big and reliable. They're less interesting because it's usually pretty obvious why they failed.

Oh? We don't even begin to have the technology to create a self-replicating, self-repairing machine that can be expected to last 70 years or so of active service. One that slowly gets better over time as the error-prone replication turns up the odd improvement.

You should not look at 'life' as single organisms but as a system of organisms and as such it is very reliable. Once it started it lasted for billions of years, and over time managed to exhibit an extreme shift in complexity using roughly the same basic mechanisms.

The only things we've made that are more reliable than life are buildings that don't move (and are still prone to catching fire every now and then), anything with moving parts needs constant maintenance to get even a couple of years of use out of it.

The answer to a slightly different question is quite simple: how did life get so reliable? First, we should define what it is that it is reliable at. Particular organisms are, of course, far from reliable, but if we look at life as a whole, it is very reliable in doing one thing: ensuring that at any time there's at least a single copy of the program (genetic matter) that is in a runnable condition. How is it so reliable at that?

1. The goal is rather simple. 2. The time and energy (the computational effort) required to arrive at that first viable self-replicating molecule was huge. 3. The computational effort of the constant required maintenance is also similarly huge.

Thank you for understanding. Both the OP's and my question are interesting. Considering both together is sublime.

Life is not reliable.

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