"some crackpot pet theory of my own that says "Oh, the chances against any aliens being humanoid are very, very high!"

Much as I'd like to take the credit for this theory, it's not mine. A simple study of the processes of natural selection and evolution might well lead you to the same conclusion. We can't know how many forms of life there are in the universe, and even attempts to calculate the figure have been the subject of some debate (the Drake equation has been questioned recently - as it should be).

"That's bullshit. It's just an argument of convenience which jumps into your mind, because you would rather not believe that anyone has seen any aliens, period, and you're looking for any excuses you can think of to pooh-pooh various eyewitness accounts."

Er, easy now, no need to get leery - this is a debate right? This argument hasn't jumped in my mind for the sole purpose of disagreeing with you LH, I've spent time looking at the facts and I've thought about it. I have taken an interest in this subject since I was a boy when I would have agreed with you, but opinions change. I keep an open mind on whether anyone has seen aliens, but I'll decide for myself how valid any of these testimonies are myself, thanks.

The small amount of learning I've done in my main field of interest outside work (in geology and palaeontology) taught me the basic scientific principle of question everything. Reach your own conclusions based on reviewing the available evidence and literature and interpret the data as honestly as possible.

Perhaps I'll go - by not agreeing I'm obviously upsetting you.