Science depends upon perception and inference ; its credibility is due to the fact that the perceptions are such as any observer can test. The mystic himself may be certain that he knows, and has no need of scientific tests ; but those who are asked to accept his testimony will subject it to the same kind of scientific tests as those applied to men who say they have been to the North Pole. Science, as such, should have no expectation, positive or negative, as to the result.
Source: Religion and Science, 1935, chapt. 7
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