I would definitely say biological viruses are a life form. They use as a substrate. However, you need the ability to mutate in order to evolve. Computer viruses can't do that at the moment, they are dumb machines/tools that just keep doing the same thing over and over until we wipe them out.
IMO, self-replication is the most fundamental characteristic, and the ability to mutate/evolve is key as well. The rest is all details.
The "metabolism" requirement is an important one, though. If you remove it, and you allow for "self-replication" that's entirely dependent on an external agent, then it seems like you would have to consider all kinds of things as "alive" that would fall outside any common-sense definition of the term. For example, works of literature.
It seems to me literature doesn't self-replicate, we replicate it... And apart from the bible and such, literature usually dies out fairly quickly in the grand scheme of things.
Viruses rely entirely on the host cell's proteins for all of their replication. They don't metabolize anything themselves, nor do they create their own copies of themselves. The host cell creates copies of the virus.
I agree with the other responder. However, humans stopping evolving seems unlikely to happen. For instance, right now, we have birth control. Birth rates are declining rapidly. I don't think that's going to continue. We are in the process of selecting for people who have more children. Nature will find a way to evolve around birth control.
Both you and the other responder just completely ignored my question though. I'm not asking if humans will stop evolving or if other species have gone extinct. I'm saying that if we somehow used CRISPR to stop genetic mutation (let's assume it's possible), but in every other way remained the same, are you saying we would no longer be life?
I'm asking this question because the aforementioned definition of "life" is flawed in my opinion. Evolution has nothing to do with it.
1. Unless you have some way to stop time, it is impossible to stop humans from mutating/evolving.
2. I would argue it is part of being human, and being alive, to evolve and adapt to your environment. Humans have multiple ways of doing this. Beyond our ability to genetically evolve, our intelligence is a mechanism we use to adapt to your environment much faster than genetics permit.
IMO, self-replication is the most fundamental characteristic, and the ability to mutate/evolve is key as well. The rest is all details.