Everyone feels like that can tell you what “life” is. It is pretty obvious. Well, unless you get near the edges of the definition.
My son just started High School here in the USA and is taking his first biology course. One of their first assignments was to decide if a virus is alive. My poor boy had to put up with his ‘ole man lecturing him on the arbitrary nature of the word “life”. He felt that “life” was an idea that needed to be discovered, but quickly saw that “life” is not a concrete thing, but an abstract word created by people that masquerades as a concrete thing.
He soon realized that to decided whether a virus was a form of life, he needed an arbitrary man-made definition of “life”. Next, he saw that the definitions everyone put forth were fuzzy and loaded with assumptions.
Like the words “religion” and “patriot”, people generally feel they know exactly how to use the word “life” and intuitively know what it means until they are up against things on the edge or people who don’t agree with their use of the word.