In theory wouldn't that cover any organism that subsists directly on a non-living energy source (forgot if there's a word for that). Plants with the sun, deep-s

In theory wouldn't that cover any organism that subsists directly on a non-living energy source (forgot if there's a word for that). Plants with the sun, deep-sea life with thermal vents. If you go full sci-fi, I imagine a human could survive without the expense of another living thing if we could synthesize all the nutrients etc that a human needs. As to why it matters in a philosophical sense, I'd say it doesn't. Everything's just matter and energy. But it matters to some people so they try to reduce their impact, just like violence matters to most people so most people try to avoid injuring or maiming people, even if it doesn't matter in the end.