The point was to make a clearly after-the-fact definition that works, but doesn’t say anything interesting. There may not be any exocritters that use some other macromolecule for their genetic material. If not, it would be a non-issue, right?
It would still be an issue if we started making synthetic life. A good definition ought to cause as little inconvenience as possible. I agree that life isn’t fundamentally different from all other matter, but the reason we have the word at all is because it’s handy to be able to encapsulate it as a reference class. Individuals with a solid grounding in natural sciences may at least be at a state of “I know what I mean when I talk about it,” but if we are going to define it at all rather than simply taking the Justice Stewart approach, the definition should encapsulate what we actually mean.
I agree that life isn’t fundamentally different from all other matter, but the reason we have the word at all is because it’s handy to be able to encapsulate it as a reference class.
I think the reason we have the word is more to do with historical vitalism than with carving reality at its joints. These days it’s most often, or at least most rigorously, used to indicate “that thing biologists study, with all the membranes and nucleotides and amino acids.” If you want to be more abstract than that, I don’t think trying to define “alive” is really a good approach at all, because it means too many different things. But you can certainly look at all the interesting things it can mean and figure out which one you’re currently talking about. You might want to give it a new name, though.
It would still be an issue if we started making synthetic life. A good definition ought to cause as little inconvenience as possible. I agree that life isn’t fundamentally different from all other matter, but the reason we have the word at all is because it’s handy to be able to encapsulate it as a reference class. Individuals with a solid grounding in natural sciences may at least be at a state of “I know what I mean when I talk about it,” but if we are going to define it at all rather than simply taking the Justice Stewart approach, the definition should encapsulate what we actually mean.
I think the reason we have the word is more to do with historical vitalism than with carving reality at its joints. These days it’s most often, or at least most rigorously, used to indicate “that thing biologists study, with all the membranes and nucleotides and amino acids.” If you want to be more abstract than that, I don’t think trying to define “alive” is really a good approach at all, because it means too many different things. But you can certainly look at all the interesting things it can mean and figure out which one you’re currently talking about. You might want to give it a new name, though.