On: A 1990 experiment to test whether we could discern...

[s1artibartfast]

So maybe to be alive you can't use any external interpretation. It pushes the threshold up, but basically all cellular life decoders it's own DNA. The environment is just materials and I formation. No decoding

[kragen → s1artibartfast]

you run into the reprap vitamin problem: is vitamin b12 'just materials' or is it 'decoding'? but afaik all cellular life encodes its own ribosome proteins in its dna or rna, rather than harvesting ribosomes from prey, so in that sense it encodes its own decoder

would a hypothetical https://en.wikipedia.org/wiki/Mycoplasma_genitalium variety that harvested ribosomes from eukaryotic cells no longer count as 'alive'? it's already an obligate parasite

how about https://en.wikipedia.org/wiki/Nasuia_deltocephalinicola? it depends on its insect host for atp

[s1artibartfast → kragen]

I think you could argue that b12, ect are just materials in the sense that the consumer is not providing inormation for its manufacture.

In this case where manufacturing instructions are transmitted, you could have a system where neither component is consider alive by itself, but the system is.

One cell with DNA only, and another with ribosomes only would not be considered alive. However, a multicellular combination of them would be alive.

Obligate parasites will be alive in some cases, and not in others, depending on how they handle stored data (DNA), and what they rely on the host to do.