A story about a patient who was convinced he was dead

The psychiatrist asked him "Do dead men bleed?" and the patient said "No, they don't." So the psychiatrist stuck the patient with a pin and made him bleed. The patient looked at the blood and said, "By golly, dead men DO bleed!"

My point is that you can't argue anyone out of a belief.

A true believer won't listen to you.

They will insist their own intuition and experience outweigh any amount of external proof and evidence.