Much has been written in the last 50 years on the psychology of the witch. It seems obvious, on the evidence of the trials and personal testimonies that in every era a number of people who were accused of witchcraft did believe they to be witches.

Some came even sometimes spontaneously to confess their “crimes”, feeling persecuted or abandoned. We find in much of these cases the symptoms of the classical psychosis, which are senility characterized by delusions as to her own importance and powers.

Frequently, as much emotional abnormality, irrationality and sheer ill will was displayed by the inquisitors, witch-hunters and victims of witchcraft as by the witches themselves.

Even if the number of real cases of mental illness was very low at the time, one isolated case in a town could have excited the milder more generalized but equally irrational paranoid tendencies and prejudices found among otherwise sane members of the community. In such a tense and macabre time, it was easy to raise the fear and justify any individual and collective disaster by the devil’s hand.

In every society and era, there are a certain number of people who believe themselves harmed or threatened. The paranoiacs who today believe that “they” (the police, the government, the aliens, the Jews, the Blacks, the American,) are conspiring against him or his society are the same man as the suspicious citizen of past centuries who accused witches.

The focus of the paranoia may vary with times and beliefs but the type of emotions remain constant: the desire to suppress the object of fear. Unchanging too is the paranoid tendency to assign the evil not just to one individual’s malevolence but also to an organized conspiracy of ill-doers; hence the collective prejudice against a mythical-secret society of Jews, witches or aliens.

Other constant features include the physical differences between the scapegoat-group and the norm and their plot to multiply their number in order to gain control over society.

Since it was also believed that witches could “shape-shift”, go forth in the spectral form and send their own spirits or those of attendant demons out to inhabit hapless bodies, a plea that somebody was possessed could also be regarded as a protestation of innocence.

“Unvolontary possession” could also be considered as legal defense and a let-out. This process was used by Johannes Wier, the father of modern psychiatry, to defend accused witches. In De Preastigiis Daemonum” he blamed the “uninformed and unskilled physicians» for attributing to witchcraft all the disease they were not able to cure.