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What Is Life? (2019)
11–20 of 117 posts
Re: What Is Life? (2019)
#12Re: What Is Life? (2019)
#13Re: What Is Life? (2019)
#14A blip between 2 ethernal nothingness.
And, what a "blip"!!
Re: What Is Life? (2019)
#15In the book Sapiens there was an interesting thought that life is basically information that is trying to "survive". In the same way you can look at religion as some sort of information that spreads in people minds and without people it would ceise to exist or have even reasons to exist - the same way like a virus is just information that goes from host to host. Viruses can represent the simplest form of what life is actually trying to achieve. I am over simplifying that part of book, but it definitely gave me an interesting different look on life.
Re: What Is Life? (2019)
#16> "And we may also wonder if a sentient computer program might one day be called alive of course" Why does a computer program have to be sentient to be called alive?
Life is metabolism, so a computer program or a silicon-based intelligence cannot be considered alive by current definition. Either we rework the definition or it will definitely not be alive. Also, sentience and intelligence are two very different things, I think we are very far from having ethical problems with switching off computers (if ever).
Re: What Is Life? (2019)
#17In the book Sapiens there was an interesting thought that life is basically information that is trying to "survive". In the same way you can look at religion as some sort of information that spreads in people minds and without people it would ceise to exist or have even reasons to exist - the same way like a virus is just information that goes from host to host. Viruses can represent the simplest form of what life is…
Yes I've long thought that the actual unit of evolution is not the gene but instead the "pattern". Genes are merely a conduit for information. Even through artificial selection, we can "select out" genes we don't want. What remains? What survives? A pattern.
Re: What Is Life? (2019)
#18My own personal definition of life is the following, somewhat hand-wavy, theoretically weak, though pragmatically strong definition:
Life is anything capable of sloppy self-replication in a sufficiently complex environment.
Viruses are definitely alive. Something like Tierra [1], Avida[2], or modern variants[3] of mutating copying programs come close, giving rise to whole ecosystems of parasites and hosts and defenses, etc. though perhaps they are lacking the "sufficient complexity" necessary so as not to stall out and stop evolving much. Chemistry provides such a massive environment of complexity that it's hard to replicate elsewhere, though I'd argue it's hardly impossible.
The problem with this article's definition is that, with near certainty, the first progenitor lifeform on earth did NOT utilize ANY of the DNA/RNA protein translation machinery they state are necessary to meet their definition of alive. You can find some surpringly good statistical analyses of this assertion in an unlikely ally: creationist statistical arguments. They prove pretty definitively that life didn't begin with a transcriptase protein popping into existence.
What are the problems with my definition:
The big theoretical hole: You could concoct some hypothetical scenario where something I'd definitely agree is alive replicates using some star trek technology that doesn't allow for the "sloppy" part. W/e, I consider this pragmatically irrelevant.
The second big objection: It allows us to consider many things as "alive" that most would say are not. In my opinion, this is actually a major strength.
Ok, but what about things like crystals? Personally, I consider some type of self-catalysing crystal or quasicrystal to be one of the most plausible forms of original life on earth. That said, they seem to be lacking the "sufficient complexity" aspect. However, are they really? I'm not so sure. Is it possible for a particular pattern of crystal defects to bring about a replication of sorts of that defect pattern elsewhere in the crystal during crystallization? That may be enough complexity particularly when you consider substitutions (when one element in the crystal lattice gets swapped for another). If some type of pattern of crystal defects or quasicrystal or something developed sufficient self-catalysing ability to bring about a form of sloppy self-replication, it's likely that's enough for life provided that the environment allows it under entropy considerations.
[1]https://en.wikipedia.org/wiki/Tierra_(computer_simulation) [2]https://en.wikipedia.org/wiki/Avida [3]https://en.wikipedia.org/wiki/Artificial_life
Re: What Is Life? (2019)
#19A blip between 2 ethernal nothingness.
We haven't even figured out what time is. So basing definitions on it seems premature.
Re: What Is Life? (2019)
#20I think it's reasonable to recognize genetic replication as being a defining feature of life on earth as we know it today, without ruling out discovery or invention of other possibilities in the future.
If you brought me a blob of something and ask me whether it contained "life," I'd analyze it for DNA or RNA. In the absence of those things I'd look for a preponderance of chirally selected molecules.