Are you asking "how do you define life?" or "how do you separate organisms from each other?"? Regarding either question, I don't think anybody has a good answer

Are you asking "how do you define life?" or "how do you separate organisms from each other?"? Regarding either question, I don't think anybody has a good answer, and that's what's so fascinating, because it really seems to be a metaphysical question rather than a scientific one.