The Mediums, and the Ideomotor Answer

Automatic writing was the workhorse technique of nineteenth and early twentieth century Spiritualism, and it generated an enormous body of material, some of it of genuine literary and psychological interest.

The most ambitious project built on it was pursued by researchers at the Society for Psychical Research, who collected scripts produced independently by several automatists in different countries over some three decades. The claim was that fragments in different scripts were meaningless alone and fitted together into classical allusions when combined, which was offered as evidence of a single discarnate intelligence coordinating them. Sceptics answered that the fragments were interpreted by people who knew what they were hoping to find, and that with enough text and enough erudition connections can always be constructed.

A separate and unusually careful case concerned a Swiss medium who produced an entire language, script and cosmology attributed to Mars. The psychologist who studied her demonstrated that the language was built on the grammar of her own native French, and treated the whole production as an achievement of an unconscious creative faculty rather than as fraud or as contact. It remains a model of how to take a phenomenon seriously without accepting its own account of itself.

The mechanism generally accepted is the ideomotor effect, in which expectation produces small muscular movements the person does not experience as their own. The same effect drives the pendulum and the planchette.