Imagine a “primordial soup” on some planet somewhere from which there occasionally emerges a thing that could locomote, and as it locomoted around it would scrape up some of the dust that lay around on the planet, and occasionally eat other things that had come out of the “primordial soup” and it would thus grow. Eventually it would wear out as its molecules, put together by some chemical process of abiogenecis in the aforementioned soup, and thusly worn out, molecules broken down by ultraviolet rays from the nearby star, it would eventually stop moving and remain exposed to the elements and dry out and become part of the dust, to be scraped up and consumed by other things.
Imagine that dozens of shallow seas of primordial soup on this planet each produced a range of such things, and they moved around on the planet, some staying in the soup, some going onto land, interacting, competing, cooperating, eating each other, sliding past each other, being born of the soup and dying, the dust sometimes being blown back into the soupy seas or being scraped up by other things.
The things are alive, right?
What if there was a form of thing on some other planet that had crawled out of the ooze and over time evolved, changed, varied, but over even longer periods of time, a self replicating version of this thing, or set of things, developed a way of perfectly identifying copies of itself that were not perfect, and destroying them. Say this emerged in several lineages of things, and this invariance gave some advantage to the things that did this. All other things, the ones that vary and change over generational time, are out-competed and those lineages disappear. So eventually, there are dozens of lineages of distinct but invariant things walking, sliding, coasting, flying, around on the surface of this planet, replicating but always duplicating perfectly, for hundreds of thousands of generations.
These things are alive, right?
Not according to Edward Trifonov, who defines life as:
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