This is a much more interesting question, and this is what I mean by an operational definition of life. In your first question, "alive" can have useful operatio

This is a much more interesting question, and this is what I mean by an operational definition of life. In your first question, "alive" can have useful operational definitions -- whether it is viable outside of a cell, whether it has or had its own immune system and structure, how it survived without the organelles that other full-fledged cells seem to have but mitochondria lack, etc. The question in the abstract is not really useful except to answer trick questions in bar trivia.