It’s arguably much harder to believe something absolutely without clear proof.
Lies That Scientists Tell (Themselves)
Martin Rezny
3618

Also impossible to disprove. In that respect the religious have the upper hand and always will. Theoretically it should always be possible to change the mind of the scientist. All you need do is muster enough evidence and he must alter is position or he has abandoned his principles. There is no possible evidence that could alter the mind of the true believer.