Further aside: Viruses themselves may not even be life!

B can be A, without A being B ;)

I had this exact example in mind tho FWIW. It is an ongoing research topic whether or not viruses are life, but the analogies/similarity are overall worth noting.

Maybe on a biosphere level, or even on a more micro ecosphere level, all sentient systems really exhibit the same properties as a virus in the local context, for that system, even if entities in that system do not have the consciousness to be able to make that determination. Certainly our effect on the planet Earth since the Industrial Era should make it worth it to endeavour this analysis!

Can I interpret it like this?

human 'is' set; human set 'has' man | woman; man 'is' human but not human 'is' man

virus 'is' set; virus set 'has' life; life 'is' virus but not virus 'is' life

Viruses (the specific scientific concept and their instances in the world) are not alive by most mainstream scientific descriptions. This is mainly because they lack genetic code to implement metabolism.

So they're kind of like an abstract base class of life that is missing an implementation of metabolize()

More like abstract method or protocol or prototype one has to implement for any life base class.

But probably You have an virus object just have a subset of the base class.

Of course if you have a class system that allow multiple inheritance that it will be one of the crucial base classes.

Under lisp ...

Let us stop.

In this particular case it is not really a virus: “ Mitogen interacts with many aspects of the operating system, threading, SSH, sudo, sockets, TTYs, shell, Python runtime, and timing and ordering uncertainty introduced through interaction with the network, GIL and OS scheduling.”

It is more like a networked python program calling shell ;-).

Problem is usually virus is assembler level or C bare metal or minimum dependence on certain aspect of host Env. All virus is small. A subset.

All life are virus+. The issue at stake you have to find a way of reproduction sort of on your own. No remote manager etc. But just virus, possibly no. Biological it cannot even reproduce without host.