The "spiritualistic" movement spread like an epidemic. "Spirit circles" were soon formed in many families.
In truth, Schopenhauer's conception of the world as the activity of a blind force is at bottom a materialistic and mechanical rather than a spiritualistic and teleological theory.
Spiritualism has been accused of a tendency to produce insanity, but spiritualistic sittings carried on by private persons do not appear to he harmful provided those who find in themselves "mediumistic" powers do not lose their self-control and exercise these powers when they do not desire to do so, or against their better judgment.
Under the pressure of this strain "spiritualistic" phenomena began to appear.
He gives an ecclesiastic's account of the First Crusade, and is specially full on the spiritualistic phenomena which accompanied and followed the finding of the Holy Lance.