I do think it is important to remember that no matter what facts we solicit to support any argument about the prospect of life or indeed intelligent life in other places besides on Earth that we are merely engaged in speculation.
I believe life will be common place but again that is speculation and no matter what logic I present to support such a belief one (myself) must remember that I simply dont know the answer and never will.
As to intelligence being related to tool use I suggest that there are many humans that may not be considered intelligent if such a test is applied ..lets face it primitive man could round up a feed from the bush but these days put someone out of range of a super market and they will die from starvation.
I have no doubt that those considered above most of us probably have never even prepared a meal for themselves let alone caught it or attended to its growth. Could the Queen of England make a sandwich I wonder?
It would be very confronting if it could be established beyond doubt that life only existed on this planet ..consideration along these lines would leave one feeling either very special or merely some kind of accident.
alex
