I don't think there are many scientists who think our current understanding of the universe is the final one.
(In the field of religion however...) we require knowledge behind a ‘veil of perception’, an occult field of ‘appearance’ which leaves us ignorant of the reality presumed to be beyond.
A hallucination may occur in a person in a state of good mental and physical health, even in the apparent absence of a transient trigger factor such as fatigue, intoxication, or sensory deprivation.
It is not yet widely recognised why hallucinatory experiences occur spontaneously in a significant proportion of normal population not undergoing particular stress or other abnormal circumstance.
The evidence for this statement has been accumulating for more than a century.
