Physiological Challenges
Counter: there is no evidence that every person who has had a religious experience was suffering from an illness
Psychological Challenges
Sociological Challenges
Counter: Marx could not accept that for many people religion is more than a comfort, it is a relationship with God
Chemicals
Mind altering chemicals:
e. g. St Francis Xavier’s diet was deficient in Vitamin B - it could be argued that the ‘heavenly visions’ he had were simply hallucinations
- alcohol
Other minds
we can never truly know what someone else thinks
Sincerity
They may be sincere but mistaken
David Hume
believed that people add details when they tell their own tales, so after repetition, the teller remembers what they said rather than what they experienced - mistrust in memories