A further result of the innate characteristics and tendencies of the feeble-minded is to be found in the effect upon them of the biological law of natural selection, resulting from the universal struggle for existence and the survival of the fittest. We need not discuss here its profound influences, economic and otherwise, upon the lives of the mentally defective in general, but it will be profitable to review briefly the effect of natural selection upon the juvenile delinquent group.
Any group of delinquents is subject to this selection from the times of offenses to final commitment. It undergoes a constant sifting process whose operation is mainly determined by the natural consequences of the group members; a large proportion of the "lucky," the intelligent, or the socially favored individuals escape from the group, so that the remaining members of the group are the least fit socially and intellectually. The mentally defective delinquents constitute an undue proportion of this unfit residue, for although they may receive as many favors of chance as do their intellectually normal fellow-delinquents, they cannot, like them, by reason of intelligence or social status, escape the consequences of their delinquent acts. Furthermore, the feeble-minded offender is caught oftener than are his more clever and energetic companions of normal endowments, and after apprehension he is less likely to receive the benefits of police and court prejudices, or the advantages of family wealth and social influence. If placed on probation he is more likely to fail, because of his own weaknesses and his unfavorable environment. Hence the feeble-minded delinquent is much more likely to come before the court and also to be committed to a reformatory, jail, or industrial school than is his companion of normal mind. Therefore practically every group of juvenile delinquents which ultimately reaches commitment will have a very different aspect with regard to its proportion of mental defectives from that larger group of offenders, apprehended or non-apprehended, of which it was once a part. In fact, it is doubtful if any group of apprehended, detained, or probationed offenders can be said to be representative, or at least to be exactly representative, of the true proportion of mental defectives among all delinquents. Except where specific types of legal procedure bring about the elimination of the defectives, it seems as if it must inevitably result that the operation of natural selection will continually increase the proportion of mental defectives above that existing in the original group.
This factor of natural selection has not to our knowledge been given adequate consideration in any published investigation on delinquency. But if our estimate of its effects is at all justified, then most examinations of juvenile delinquents, especially in reform and industrial schools, have disclosed proportions of mental defectives distinctly in excess of the original proportion previously existent among the entire mass of all offenders. The reports of these examinations have given rise to quite erroneous impressions concerning the extent of criminality among the feeble-minded and its relation to the whole volume of crime, and have consequently led to inaccurate deductions. The feeble-minded are undoubtedly more prone to commit crime than are the average normals; but through disregard of the influences of this factor of natural selection, as well as of others, both the proportion of crime committed by mental defectives and the true proportion of mental defectives among delinquents and criminals have very often been exaggerated.
D. ISOLATION AND NATIONAL INDIVIDUALITY
1. Historical Races as Products of Isolation[112]
The continent of Europe differs from the other great land-masses in the fact that it is a singular aggregation of peninsulas and islands, originating in separate centers of mountain growth, and of enclosed valleys walled about from the outer world by elevated summits. Other continents are somewhat peninsulated; Asia approaches Europe in that respect; North America has a few great dependencies in its larger islands and considerable promontories; but Africa, South America, and Australia are singularly united lands.
The highly divided state of Europe has greatly favored the development within its area of isolated fields, each fitted for the growth of a separate state, adapted even in this day for local life although commerce in our time binds lands together in a way which it did not of old. These separated areas were marvelously suited to be the cradles of peoples; and if we look over the map of Europe we readily note the geographic insulations which that remarkably varied land affords.
Beginning with the eastern Mediterranean, we have the peninsula on which Constantinople stands—a region only partly protected from assault by its geographic peculiarities; and yet it owes to its partial separation from the mainlands on either side a large measure of local historic development. Next, we have Greece and its associated islands, which—a safe stronghold for centuries—permitted the nurture of the most marvelous life the world has ever known. Farther to the west the Italian peninsula, where during three thousand years the protecting envelope of the sea and the walls of Alps and Apennines have enabled a score of states to attain a development; where the Roman nation, absorbing, with its singular power of taking in other life, a number of primitive centers of civilization, grew to power which made it dominant in the ancient world. Sicily, Sardinia, Corsica, have each profited by their isolation, and have bred diverse qualities in man and contributed motives which have interacted in the earth's history. Again, in Spain we have a region well fitted to be the cradle of a great people; to its geographic position it owed the fact that it became the seat of the most cultivated Mahometanism the world has ever known. To the Pyrenees, the mountain wall of the north, we owe in good part the limitation of that Mussulman invasion and the protection of central Europe from its forward movement, until luxury and half-faith had sapped its energies. Going northward, we find in the region of Normandy the place of growth of that fierce but strong folk, the ancient Scandinavians, who, transplanted there, held their ground, and grew until they were strong enough to conquer Britain and give it a large share of the quality which belongs to our own state.
To a trifling geographic accident we owe the isolation of Great Britain from the European continent; and all the marvelous history of the English folk, as we all know, hangs upon the existence of that narrow strip of sea between the Devon coast and the kindred lowlands of northern France.
East of Britain lie two peninsulas which have been the cradle of very important peoples. That of Sweden and Norway is the result of mountain development; that of Denmark appears to be in the main the product of glacial and marine erosion, differing in its non-mountainous origin from all the other peninsulas and islands of the European border. Thus on the periphery of Europe we have at least a dozen geographical isolated areas, sufficiently large and well separated from the rest of the world to make them the seats of independent social life. The interior of the country has several similarly, though less perfectly, detached areas. Of these the most important lie fenced within the highlands of the Alps. In that extensive system of mountain disturbances we have the geographical conditions which most favor the development of peculiar divisions of men, and which guard such cradled peoples from the destruction which so often awaits them on the plains. Thus, while the folk of the European lowlands have been overrun by the successive tides of invasion, their qualities confused, and their succession of social life interrupted, Switzerland has to a great extent, by its mountain walls, protected its people from the troubles to which their lowland neighbors have been subjected. The result is that within an area not twice as large as Massachusetts we find a marvelous diversity of folk, as is shown by the variety in physical aspect, moral quality, language, and creed in the several important valleys and other divisions of that complicated topography.