I'm not a scientist, but I can tell you that I was brainwashed into believing that life must follow this set of rules to be classified as life: Life must have a lifespan. be made of cells (???) reproduce. respond to the environment. (other things on wikipedia) By this set of rules, life barely manages to qualify itself in some forms. Fire can't be defined as a life form because it destroys itself very much and is made of burned molecules and fuel. I don't say that life may or may not be life, I say that the origin of life is simple and the criteria to determine whether a planet may have life depends on what we know about where life can come from, and where it can support itself sufficiently. Only science can give an answer to that.