So if you can't prove it it must not be true? Like God's existence perhaps? Or WMD's?
I can prove that Bush, Cheney, Rummy, Powell and Condi have all said things that later turned out to not be true. I can also prove that they then blamed agencies for these false statements. I can further prove that Bush appointed the heads of those agencies. After blaming the agencies for providing him false intelligence he turns around and awards medals. Hmmmmm.....I'm thinking....yup...a pack of bald faced lies. But can I prove beyond a shadow of a doubt that the above mentioned were only naive idiots versus evil liars? No I can't. No $5K for me.