I don’t think you can reason people out of positions they didn’t reason themselves into.
This is much older than Ben Goldacre. The earliest appearance known to wikiquote is in 1851, in Scientific American. The origin is unknown.
It also sounds like Deep Wisdom. Let's try a few variations:
Once a man's reasoned himself into something, the Devil himself won't reason him out of it.
-- this might be plausibly attributed to Thomas Edison.
No faith can long survive the light of thought,
Which as the salt sea eats away the iron:
However stoutly it may seem to stand
It yields to sleepless rust and falls apart.
When Epicurus "Atoms!" spoke, that ligh...
Another month, another rationality quotes thread. The rules are: