National Geographic : 1903 Oct
GEOGRAPHICAL DISTRIBUTION OF INSANITY Wright, however, does not go into details nor discuss the causes that have led to this condition of affairs, except tosay: "ThereasonofthisIthinkto be that new settlements are made by a selected population, mostly young and middle aged people of sound minds and bodies. The insane are left behind, as are also those people of bad organiza tions, from whose numbers the most of the insane will come. The new coun tries therefore have a small proportion of insanity at the start, and furnish a small proportion of insanity in the first generation. " The only exception to this is in the case of the Pacific slope and a few other localities, where masses of homeless men, with few women and children, have gone in search of work or wealth ; where the vices of drunkenness and licentiousness, with the irregularities and the hardships of life in mining or lumbering camps, and the excessive fluctuations of fortune, have caused an excess of insanity. In these cases it is, however, to be remembered that this is a disease of mature life; and if we add the proper proportion of children who would be found in an ordinary commu nity, and who rarely have insanity, we should at once halve the ratio of in sanity in such communities. " But, in ordinary settlements, where the settlers found homes and live under the ordinary conditions of life, the ratio of insanity in the first generation is small, because they are, as the insur ance men would say, 'selected lives.' In the second generation all the com plex and varied causes which produce insanity have been at work ; and the second generation has a much greater ratio of insanity than the first, and so on for several generations, when the balance is restored and the regular rate of insanity is reached." After all this, however, Wright says: "It is often claimed that insanity is a disease of civilization, and that it is in- creasing because civilization is increas ing. This I think to be a mistake." Although this is not a very happy way to express it, it seems to me that our figures prove just that, or rather if they do not prove that insanity is the neces sary result of civilization, they at least prove that the civilized state offers those conditions in greater number which bring it about, and so if the connection be not one of necessity, it is at least one of fact. Instead, therefore, of at tempting to account for insanity by altitude, temperature, and the various other elements of the physical environ ment, we should only consider these factors as important because of their influence in creating conditions favor able to the growth and concentration of population and the evolution of the social organism. Even here this influ ence is often secondary or accidental. As regards this whole matter of the influence of the physical environment on population, I can do no better than quote Mayo-Smith,* who, in answer to the question, " How far can the statis tics of distribution be said to contribute an answer to the question of the influ ence of physical environment upon pop ulation ? " says : " Statistics show us, in a large way and on a grand scale, the general influ ence of land, climate, and natural forces upon population. The plains attract, the mountains repel. Cold regions are unpopulated. Moist and warm climates are fatal to human life. Commercial position attracts cities. Navigable riv ers are natural highways, and are util ized in the migrations of the human race. An indented seacoast is favor able to settlement and colonization. Statistics confirm the general observa tions of history. Levasseur, after a long survey of the topography of France and the history of its population, says that at all periods Paris has been the attract ive pole and the mountainous region of * Ibid. 37'