When people say, "Anything is possible," they're confusing two different meanings of the word
possible. These are sometimes distinguished as "logically possible" versus "actually possible." The former simply means that the idea can be imagined without self-contradiction; am empiricist might want to add that the idea must also be testable, at least in principle. The latter, on the other hand, means that the thing can actually happen. If we allow that something is logically possible, we're simply saying that we can imagine circumstances that would cause us to believe that it's happened; if we say it's actually possible, that means we believe it has happened, or at least is bound to happen given sufficient opportunity.
Eric
Gondwanaland --
http://stripey7.blogspot.com