|MadSci Network: Chemistry|
This is not a bad question at all! I think it comes from algorithmic application of empirical rules; I believe Gödel's Theorem pretty thoroughly discredited that mode of inquiry by showing that it was always possible to make true statements within a given system which are not provable within that system. You have to stand outside the rules in order to answer, "No, fire is not alive." We think of something alive as displaying, for example, "volition" (and I use quotes deliberately), meaning that its behavior is not easily predictable. Fire does not display "volition."
For that matter, the same sort of mechanical application of rules leads to doubt about whether viruses are alive, and the answer comes from the same sort of reasoning "outside the rules." In the case of viruses I think the answer is much more ambiguous than it is for fire, but I'd bet most virologists consider the question more-or-less meaningless. For what it's worth -- virology is quite my area of expertise -- I think viruses are alive.
(For more information about Kurt Gödel, try the Gödel Society's home page.)
Editor's Note: The link to Godel's Theorem above works, but it appears to be lacking some of its supporting web pages. There is, however, a link to an essay called Godel for Dummies which helps explain the theorem.
Try the links in the MadSci Library for more information on Chemistry.