The mind and the body reciprocally and mysteriously affect each other, and the maladies which are the subject of these pages, are so intimately connected with the disordered state of both, that it is often difficult to determine on which they more essentially depend, or which they more seriously influence.
The physician will probably be led by their contemplation to admit that the imagination has a larger share in the production of disease than he might, without a knowledge of the striking facts here recorded, have supposed to be within the limits of possibility. He has, no doubt, already observed, that joy will affect the circulation, grief the digestion; that anger will heat the frame as perniciously as ardent spirits, and that fear will chill it as certainly as ice; but he may not have carried his observation to the extent of perceiving, that not only single and transient effects, but specific diseases are produced through the agency of mental impressions, and he may therefore still be surprised to find that the dances of St. John and of St. Vitus, as they formerly spread by sympathy from city to city, gave rise to the same deviations from bodily health, in all the individuals whom they attacked; that Tarantism was the same disease, whether medically or morally considered, all over Italy; and that the “Lycanthropia,” of the past, and the “Leaping Ague” of the present times, have each its respective train of peculiar symptoms.
The moralist will view these records of human frailty in a different light; he will examine the state of society which favoured the propagation of such maladies; he will inquire how far they have been the offspring of the ages in which they appeared, and although he may not be disposed to think with our author, that they can never return, he will at least deduce from the facts here laid before him, that they originate in those minds, whether ignorant or ill-educated, in which the imagination is permitted to usurp the power of sober sense, and the ideal is allowed to occupy the thoughts to the exclusion of the substantial.
That such minds are most frequently to be met with in an age of ignorance, we should naturally suppose, and we are borne out in that supposition by the fact, that these diseases have been declining in proportion to the advance of knowledge; but credulity and enthusiasm are not incompatible with a high degree of civilization: and if, among the educated classes, the female sex is more sentimental than the male, and the affluent are more credulous than those who are dependent on their own exertions for their support, it is to be accounted for by the fact, that they usually devote more leisure to the pleasurable contemplation of works of imagination, and are less imperatively called on to improve their judgment by the dry study of facts, and the experience acquired in the serious business of life. But there is no class, even in this age of boasted reason, wholly exempt from the baneful influence of fanaticism; and instances are not wanting, in our own days, and in this very capital, to prove, that disorders (how can we more charitably designate them?) much resembling some of those described in the following pages, may make their appearance among people who have had all the advantages of an enlightened education, and every opportunity of enlarging their minds by a free intercourse with refined society.
I thus venture to hope, that by bestowing a leisure hour on this small portion of medical history, the physician may enlarge his knowledge of disease, and the moralist may gather a hint for the intellectual improvement of his fellow-men. The author has, however, a more extended object in view—the histories of particular epidemics are with him but the data from which we are to deduce the general laws that govern human health in the aggregate. Whether there be such an entity as collective organic life, and whether, as a consequence, there exist general laws which regulate its healthy or morbid condition, I do not here undertake to determine; but the notion is peculiar, and in order that it may be more fully exposed to the reader, I have translated as an introduction to the present volume[1], an Appeal which Dr. Hecker has made to the medical profession of his own country for assistance in his undertaking. If, in the course of the remarks contained in this address, he has been somewhat severe in his censure of the neglect, both in this country and in France, of the study of Medical History, I freely confess myself to be one of those who are more anxious to profit by his castigation than to dispute its justice.
I have added a few Notes, which I trust will be found not inapplicable. They consist chiefly of parallel accounts in illustration of what is set forth in the text; and with the same view, I have thrown together in No. V. of the Appendix, some Histories of Local Epidemics, and have referred to some single cases, which seem to me to have a peculiar interest in connexion with the subject of this work, and to render it, on the whole, more complete.
PREFACE.
The diseases which form the subject of the present investigation afford a deep insight into the workings of the human mind in a state of society. They are a portion of history, and will never return in the form in which they are there recorded; but they expose a vulnerable part of man—the instinct of imitation—and are therefore very nearly connected with human life in the aggregate. It appeared worth while to describe diseases which are propagated on the beams of light—on the wings of thought; which convulse the mind by the excitement of the senses, and wonderfully affect the nerves, the media of its will and of its feelings. It seemed worth while to attempt to place these disorders between the epidemics of a less refined origin, which affect the body more than the soul, and all those passions and emotions which border on the vast domain of disease, ready at every moment to pass the boundary. Should we be able to deduce from the grave facts of history here developed, a convincing proof that the human race, amidst the creation which surrounds it, moves in body and soul as an individual whole, the Author might hope that he had approached nearer to his ideal of a grand comprehension of diseases in time and space, and be encouraged, by the co-operation of contemporaries, zealous in the search of truth, to proceed along the path which he has already entered, in prosecuting the investigation.