Basically I just want a biological definition to the term life or alive. I remember in high school biology that there were conditions (I believe there were 5) that an object must meet or pass before it can be considered alive or else it is considered to be an inanimate object (such as a rock). Although I can't remember the conditions themselves. Anyone know them? Also given the conditions, can someone explain why fire is not considered to be alive? Several years ago I remember watching an episode of Star Trek: The Next Generation (yeah yeah yeah I know, I'm a dork) where this very question came up and I believe Data explained (or maybe another member of the crew explained it to Data) why fire is not considered to be alive. Of course I forget why which is what I'm after. thanks.