In aviation they have auto pilot and color radar and a lot of other instrumentation that is a backup for pilots. It's really brought the incidents of plane crashes way down. Same thing ought to happen in the medical industry, I think.
If a man proves too clearly and convincingly to himself. . . that a tiger is an optical illusion--well, he will find out he is wrong. The tiger will himself intervene in the discussion, in a manner which will be in every sense conclusive.