The first source of error lies in the fact that the experiments of this school are made almost exclusively upon hysterical women. The assumption is that hypnotism is a nervous disease, and that the disease is found in its most pronounced form in hysterical subjects. That this proposition is unqualifiedly wrong is positively known to every student of hypnotism outside the Paris school, and needs no further refutation than the bare statement that the experience of all other schools goes to demonstrate the fact that the best hypnotic subjects are perfectly healthy persons. Another source of error lies in the fact that they ignore suggestion as a necessary factor in the production of hypnotic phenomena. Of course they are aware of the potency of suggestion when purposely and intelligently employed; but they hold that very many of the most important of the phenomena can be produced without its aid. These, however, are principally physical effects, such as causing any muscle of the body to contract by pressing upon the corresponding nerve, and then releasing the tension by exciting the antagonistic muscle. The condition necessary for the production of this phenomenon is called by Charcot, "neuro-muscular hyperexcitability." In the able and interesting work by Binet and Féré, pupils of Charcot, a chapter is devoted to this branch of the subject. They record, with a scientific exactitude that is very edifying, many curious results in the way of causing contracture of various muscles by kneading, pressure, percussion, etc., releasing the tension by exciting the opposing muscles, and transferring the contractures from one muscle to another by the magnet. Then, with an ingenuousness that is truly charming, they add, as a "singular fact," that "contractures can be easily produced in many hysterical patients in their waking state, either by kneading the muscles, by pressure on the nerves, or by striking the tendons. These contractures in the waking state are, indeed, of the same nature as those which occur during lethargy, since they yield to the excitement of the antagonistic muscles, and may be transferred by the magnet." After this admission it seems superfluous to remark that this class of experiments prove nothing more than that the state of neuro-muscular hyperexcitability is a pathological symptom common to hysterical patients, whether in the waking state or in hypnotic lethargy. They certainly prove nothing which can be construed as characteristic of hypnotism; and the Nancy school wastes its time in demonstrating that the symptoms cannot be reproduced in healthy persons except by the aid of suggestion.